File: REQUEST-920-PROTOCOL-ENFORCEMENT.conf

package info (click to toggle)
modsecurity-crs 3.0.2-1~bpo9+1
  • links: PTS
  • area: main
  • in suites: stretch-backports
  • size: 1,064 kB
  • sloc: ansic: 727; perl: 428; python: 218; ruby: 69; makefile: 15
file content (1534 lines) | stat: -rw-r--r-- 48,728 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
# ------------------------------------------------------------------------
# OWASP ModSecurity Core Rule Set ver.3.0.2
# Copyright (c) 2006-2016 Trustwave and contributors. All rights reserved.
#
# The OWASP ModSecurity Core Rule Set is distributed under
# Apache Software License (ASL) version 2
# Please see the enclosed LICENSE file for full details.
# ------------------------------------------------------------------------

#
# Some protocol violations are common in application layer attacks.
# Validating HTTP requests eliminates a large number of application layer attacks.
#
# The purpose of this rules file is to enforce HTTP RFC requirements that state how
# the client is supposed to interact with the server.
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html



#
# -= Paranoia Level 0 (empty) =- (apply unconditionally)
#


SecRule TX:PARANOIA_LEVEL "@lt 1" "phase:1,id:920011,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
SecRule TX:PARANOIA_LEVEL "@lt 1" "phase:2,id:920012,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
#
# -= Paranoia Level 1 (default) =- (apply only when tx.paranoia_level is sufficiently high: 1 or higher)
#

#
# Validate request line against the format specified in the HTTP RFC
#
# -=[ Rule Logic ]=-
#
# Uses rule negation against the regex for positive security.  The regex specifies the proper
# construction of URI request lines such as:
#
# 	"http:" "//" host [ ":" port ] [ abs_path [ "?" query ]]
#
# It also outlines proper construction for CONNECT, OPTIONS and GET requests.
#
# -=[ References ]=-
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.2.1
# http://capec.mitre.org/data/definitions/272.html
#
SecRule REQUEST_LINE "!^(?i:(?:[a-z]{3,10}\s+(?:\w{3,7}?://[\w\-\./]*(?::\d+)?)?/[^?#]*(?:\?[^#\s]*)?(?:#[\S]*)?|connect (?:\d{1,3}\.){3}\d{1,3}\.?(?::\d+)?|options \*)\s+[\w\./]+|get /[^?#]*(?:\?[^#\s]*)?(?:#[\S]*)?)$"\
  "msg:'Invalid HTTP Request Line',\
  severity:'WARNING',\
  id:920100,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'2',\
  maturity:'9',\
  accuracy:'9',\
  logdata:'%{request_line}',\
  phase:request,\
  block,\
  t:none,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ',\
  tag:'CAPEC-272',\
  setvar:'tx.msg=%{rule.msg}',\
  setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ-%{matched_var_name}=%{matched_var}'"


#
# Identify multipart/form-data name evasion attempts
#
# There are possible impedance mismatches between how
# ModSecurity interprets multipart file names and how
# a destination app server such as PHP might parse the
# Content-Disposition data:
#
#       filename-parm := "filename" "=" value
#
# -=[ Rule Logic ]=-
# These rules check for the existence of the ' " ; = meta-characters in
# either the file or file name variables.
# HTML entities may lead to false positives, why they are allowed on PL1.
# Negative look behind assertions allow frequently used entities &_;
#
# -=[ Targets, characters and html entities ]=-
#
# 920120: PL1 : FILES_NAMES, FILES
#         ['\";=] but allowed:
#         &[aAoOuUyY]uml); &[aAeEiIoOuU]circ; &[eEiIoOuUyY]acute;
#         &[aAeEiIoOuU]grave; &[cC]cedil; &[aAnNoO]tilde; & '
#
# 920121: PL2 : FILES_NAMES, FILES
#         ['\";=] : ' " ; = meta-characters
#
# -=[ References ]=-
# https://www.owasp.org/index.php/ModSecurity_CRS_RuleID-960000
# http://www.ietf.org/rfc/rfc2183.txt
#
SecRule FILES_NAMES|FILES "(?<!&(?:[aAoOuUyY]uml)|&(?:[aAeEiIoOuU]circ)|&(?:[eEiIoOuUyY]acute)|&(?:[aAeEiIoOuU]grave)|&(?:[cC]cedil)|&(?:[aAnNoO]tilde)|&(?:amp)|&(?:apos));|['\"=]" \
  "msg:'Attempted multipart/form-data bypass',\
  severity:'CRITICAL',\
  id:920120,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'9',\
  accuracy:'7',\
  logdata:'%{matched_var}',\
  phase:request,\
  block,\
  t:none,t:urlDecodeUni,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ',\
  tag:'CAPEC-272',\
  setvar:'tx.msg=%{rule.msg}',\
  setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ-%{matched_var_name}=%{matched_var}'"


#
# Verify that we've correctly processed the request body.
#
# As a rule of thumb, when failing to process a request body
# you should reject the request (when deployed in blocking mode)
# or log a high-severity alert (when deployed in detection-only mode).
#
# -=[ Rule Logic ]=-
# Checks for the existence of the REQBODY_ERROR variable that is created
# by the request body processor if it encounters errors.
#
# -=[ References ]=-
# https://sourceforge.net/apps/mediawiki/mod-security/index.php?title=Reference_Manual#REQBODY_ERROR
#
SecRule REQBODY_ERROR "!@eq 0" \
  "msg:'Failed to parse request body.',\
  severity:'CRITICAL',\
  id:920130,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'9',\
  accuracy:'9',\
  logdata:'%{REQBODY_ERROR_MSG}',\
  phase:request,\
  block,\
  t:none,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ',\
  tag:'CAPEC-272',\
  setvar:'tx.msg=%{rule.msg}',\
  setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ-%{matched_var_name}=%{matched_var}'"


#
# Strict Multipart Parsing Checks
#
# -=[ Rule Logic ]=-
# By default be strict with what we accept in the multipart/form-data
# request body. If the rule below proves to be too strict for your
# environment consider changing it to detection-only. You are encouraged
# _not_ to remove it altogether.
#
# -=[ References ]=-
# https://sourceforge.net/apps/mediawiki/mod-security/index.php?title=Reference_Manual#MULTIPART_STRICT_ERROR
#
SecRule MULTIPART_STRICT_ERROR "!@eq 0" \
  "msg:'Multipart request body failed strict validation:\
    PE %{REQBODY_PROCESSOR_ERROR},\
    BQ %{MULTIPART_BOUNDARY_QUOTED},\
    BW %{MULTIPART_BOUNDARY_WHITESPACE},\
    DB %{MULTIPART_DATA_BEFORE},\
    DA %{MULTIPART_DATA_AFTER},\
    HF %{MULTIPART_HEADER_FOLDING},\
    LF %{MULTIPART_LF_LINE},\
    SM %{MULTIPART_SEMICOLON_MISSING},\
    IQ %{MULTIPART_INVALID_QUOTING},\
    IH %{MULTIPART_INVALID_HEADER_FOLDING},\
    FLE %{MULTIPART_FILE_LIMIT_EXCEEDED}',\
  severity:'CRITICAL',\
  id:920140,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'8',\
  accuracy:'7',\
  phase:request,\
  block,\
  t:none,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ',\
  tag:'CAPEC-272',\
  setvar:'tx.msg=%{rule.msg}',\
  setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ-%{matched_var_name}=%{matched_var}'"


#
# Accept only digits in content length
#
# -=[ Rule Logic ]=-
# This rule uses ModSecurity's rule negation against the regex meaning if the Content-Length header
# is NOT all digits, then it will match.
#
# -=[ References ]=-
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.13
#
SecRule REQUEST_HEADERS:Content-Length "!^\d+$" \
  "msg:'Content-Length HTTP header is not numeric.',\
  severity:'CRITICAL',\
  id:920160,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'9',\
  accuracy:'9',\
  phase:1,\
  block,\
  logdata:'%{matched_var}',\
  t:none,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
  tag:'CAPEC-272',\
  setvar:'tx.msg=%{rule.msg}',\
  setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}'"


#
# Do not accept GET or HEAD requests with bodies
# HTTP standard allows GET requests to have a body but this
# feature is not used in real life. Attackers could try to force
# a request body on an unsuspecting web applications.
#
# -=[ Rule Logic ]=-
# This is a chained rule that first checks the Request Method.  If it is a
# GET or HEAD method, then it checks for the existence of a Content-Length
# header.  If the header exists and its payload is either not a 0 digit or not
# empty, then it will match.
#
# -=[ References ]=-
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.3
#
SecRule REQUEST_METHOD "^(?:GET|HEAD)$" \
  "msg:'GET or HEAD Request with Body Content.',\
  severity:'CRITICAL',\
  id:920170,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'9',\
  accuracy:'9',\
  phase:request,\
  block,\
  logdata:'%{matched_var}',\
  t:none,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
  tag:'CAPEC-272',\
  chain"
	SecRule REQUEST_HEADERS:Content-Length "!^0?$"\
	  "t:none,\
	  setvar:'tx.msg=%{rule.msg}',\
	  setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
	  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}'"


#
# Require Content-Length to be provided with every POST request.
#
# -=[ Rule Logic ]=-
# This chained rule checks if the request method is POST, if so, it checks that a Content-Length
# header is also present.
#
# -=[ References ]=-
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.5
#
SecRule REQUEST_METHOD "^POST$" \
  "msg:'POST request missing Content-Length Header.',\
  severity:'WARNING',\
  id:920180,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'9',\
  accuracy:'9',\
  phase:request,\
  block,\
  logdata:'%{matched_var}',\
  t:none,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
  tag:'CAPEC-272',\
  chain"
        SecRule &REQUEST_HEADERS:Content-Length "@eq 0" \
          "t:none,\
          setvar:'tx.msg=%{rule.msg}',\
          setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
          setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}'"


#
# Range Header Checks
#
# 1. Range Header exists and begins with 0 - normal browsers don't do this.
# Automated programs and bots often do not obey the HTTP RFC
#
# -=[ Rule Logic ]=-
# This rule inspects the Range request header to see if it starts with 0.
#
# -=[ References ]=-
# http://www.bad-behavior.ioerror.us/documentation/how-it-works/
#
# 2. Per RFC 2616 -
#    "If the last-byte-pos value is present, it MUST be greater than or equal to the first-byte-pos in that byte-range-spec,
#    or the byte- range-spec is syntactically invalid."
# -=[ Rule Logic ]=-
# This rule compares the first and second byte ranges and flags when the first value is greater than the second.
#
# -=[ References ]=-
# http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
# http://seclists.org/fulldisclosure/2011/Aug/175
#
SecRule REQUEST_HEADERS:Range|REQUEST_HEADERS:Request-Range "(\d+)\-(\d+)\," \
  "capture,\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'Range: Invalid Last Byte Value.',\
   logdata:'%{matched_var}',\
   severity:'WARNING',\
   id:920190,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
   chain"
        SecRule TX:2 "!@ge %{tx.1}" \
		"setvar:'tx.msg=%{rule.msg}',\
		setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
		setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}"


#
# Broken/Malicous clients often have duplicate or conflicting headers
# Automated programs and bots often do not obey the HTTP RFC
#
# -=[ Rule Logic ]=-
# This rule inspects the Connection header and looks for duplicates of the
# keep-alive and close options.
#
# -=[ References ]=-
# http://www.bad-behavior.ioerror.us/documentation/how-it-works/
#
SecRule REQUEST_HEADERS:Connection "\b(keep-alive|close),\s?(keep-alive|close)\b" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'Multiple/Conflicting Connection Header Data Found.',\
   logdata:'%{matched_var}',\
   id:920210,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
   severity:'WARNING',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}"

#
# Check URL encodings
#
# -=[ Rule Logic ]=-
# There are two different chained rules.  We need to separate them as we are inspecting two
# different variables - REQUEST_URI and REQUEST_BODY.  For REQUEST_BODY, we only want to
# run the @validateUrlEncoding operator if the content-type is application/x-www-form-urlencoding.
#
# -=[ References ]=-
# http://www.ietf.org/rfc/rfc1738.txt
#
SecRule REQUEST_URI "\%((?!$|\W)|[0-9a-fA-F]{2}|u[0-9a-fA-F]{4})" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'URL Encoding Abuse Attack Attempt',\
   id:920220,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   severity:'WARNING',\
   chain"
     SecRule REQUEST_URI "@validateUrlEncoding" \
       "setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"

SecRule REQUEST_HEADERS:Content-Type "^(application\/x-www-form-urlencoded|text\/xml)(?:;(?:\s?charset\s?=\s?[\w\d\-]{1,18})?)??$" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'URL Encoding Abuse Attack Attempt',\
   id:920240,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   severity:'WARNING',\
   chain"
     SecRule REQUEST_BODY|XML:/* "\%((?!$|\W)|[0-9a-fA-F]{2}|u[0-9a-fA-F]{4})" "chain"
       SecRule REQUEST_BODY|XML:/* "@validateUrlEncoding" \
         "setvar:'tx.msg=%{rule.msg}',\
          setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
          setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


#
# Check UTF enconding
# We only want to apply this check if UTF-8 encoding is actually used by the site, otherwise
# it will result in false positives.
#
# -=[ Rule Logic ]=-
# This chained rule first checks to see if the admin has set the TX:CRS_VALIDATE_UTF8_ENCODING
# variable in the crs-setup.conf file.
#
SecRule TX:CRS_VALIDATE_UTF8_ENCODING "@eq 1" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'UTF8 Encoding Abuse Attack Attempt',\
   id:920250,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   severity:'WARNING',\
   chain"
     SecRule REQUEST_FILENAME|ARGS|ARGS_NAMES "@validateUtf8Encoding" \
       "setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


#
# Disallow use of full-width unicode as decoding evasions my be possible.
#
# -=[ Rule Logic ]=-
# This rule looks for full-width encoding by looking for %u followed by 2 'f'
# characters and then 2 hex characters. It is a vulnerability that affected
# IIS circa 2007.
# The rule will trigger on %uXXXX formatted chars that are full or half
# width, as explained above. This %uXXXX format is passed as a raw parameter
# and is (seemingly only) accepted by IIS (5.0, 6.0, 7.0, and 8.0). Other
# webservers will only process unicode chars presented as hex UTF-8 bytes.
#
# -=[ References ]=-
# http://www.kb.cert.org/vuls/id/739224
# https://www.checkpoint.com/defense/advisories/public/2007/cpai-2007-201.html
# https://github.com/SpiderLabs/owasp-modsecurity-crs/issues/719
#
SecRule REQUEST_URI|REQUEST_BODY "\%u[fF]{2}[0-9a-fA-F]{2}" \
  "msg:'Unicode Full/Half Width Abuse Attack Attempt',\
   id:920260,\
   severity:'WARNING',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   phase:request,\
   t:none,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-iis',\
   tag:'platform-windows',\
   tag:'attack-protocol',\
   block,\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


#
# Restrict type of characters sent
#
# This is a rule with multiple stricter siblings that grows more
# restrictive in higher paranoia levels.
#
# -=[ Rule Logic ]=-
# This rule uses the @validateByteRange operator to restrict the request
# payloads.
#
# -=[ Targets and ASCII Ranges ]=-
#
# 920270: PL1 : REQUEST_URI, REQUEST_HEADERS, ARGS and ARGS_NAMES
# 	  ASCII 1-255 : Full ASCII range without null character
#
# 920271: PL2 : REQUEST_URI, REQUEST_HEADERS, ARGS and ARGS_NAMES
#         ASCII 9,10,13,32-126,128-255 : Full visible ASCII range, tab, newline
#
# 920272: PL3 : REQUEST_URI, REQUEST_HEADERS, ARGS, ARGS_NAMES and REQUEST_BODY
#         ASCII 32-36,38-126 : Visible lower ASCII range without percent symbol
#
# 920273: PL4 : ARGS, ARGS_NAMES and REQUEST_BODY
#         ASCII 38,44-46,48-58,61,65-90,95,97-122
#               A-Z a-z 0-9 = - _ . , : &
#
# 920274: PL4 : REQUEST_HEADERS without User-Agent, Referer and Cookie
#         ASCII 32,34,38,42-59,61,65-90,95,97-122
#               A-Z a-z 0-9 = - _ . , : & " * + / SPACE
#
# REQUEST_URI and REQUEST_HEADERS User-Agent, Referer and Cookie are very hard
# to restrict beyond the limits in 920272.
#
# 920274 generally has few positives. However, it would detect rare attacks
# on Accept request headers and friends.

SecRule REQUEST_URI|REQUEST_HEADERS|ARGS|ARGS_NAMES "@validateByteRange 1-255" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   block,\
   msg:'Invalid character in request (null character)',\
   id:920270,\
   severity:'CRITICAL',\
   t:none,t:urlDecodeUni,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.error_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


#
# Do not accept requests without common headers.
# All normal web browsers include Host, User-Agent and Accept headers.
# Implies either an attacker or a legitimate automation client.
#

#
# Missing/Empty Host Header
#
# -=[ Rule Logic ]=-
# These rules will first check to see if a Host header is present.
# The second check is to see if a Host header exists but is empty.
#
SecRule &REQUEST_HEADERS:Host "@eq 0" \
  "msg:'Request Missing a Host Header',\
   severity:'WARNING',\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   t:none,\
   pass,\
   id:920280,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_HOST',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/6.5.10',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var},\
   skipAfter:END_HOST_CHECK"


SecRule REQUEST_HEADERS:Host "^$" \
  "msg:'Empty Host Header',\
   severity:'WARNING',\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   t:none,\
   pass,\
   id:920290,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_HOST',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"

SecMarker END_HOST_CHECK


#
# Empty Accept Header
#
# -=[ Rule Logic ]=-
# This rule checks if an Accept header exists, but has an empty value.
# This is only allowed in combination with the OPTIONS method.
# Additionally, there are some clients sending empty Accept headers.
# They are covered in another chained rule checking the User-Agent.
# This technique demands a separate rule to detect an empty
# Accept header if there is no user agent. This is checked via
# the separate rule 920311.
#
# Exclude some common broken clients sending empty Accept header:
# "Business/6.6.1.2 CFNetwork/758.5.3 Darwin/15.6.0" (CRS issue #515)
# "Entreprise/6.5.0.177 CFNetwork/758.4.3 Darwin/15.5.0" (CRS issue #366)
#
# -=[ References ]=-
# https://github.com/SpiderLabs/owasp-modsecurity-crs/issues/366
#

SecRule REQUEST_HEADERS:Accept "^$" \
  "msg:'Request Has an Empty Accept Header',\
   chain,\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'8',\
   t:none,\
   pass,\
   severity:'NOTICE',\
   id:920310,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_ACCEPT'"
     SecRule REQUEST_METHOD "!^OPTIONS$" \
       "chain"
          SecRule REQUEST_HEADERS:User-Agent "!@pm AppleWebKit Android Business Enterprise Entreprise" \
            "t:none,\
            setvar:'tx.msg=%{rule.msg}',\
            setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
            setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"

#
# This rule is a sibling of rule 920310.
#
SecRule REQUEST_HEADERS:Accept "^$" \
  "msg:'Request Has an Empty Accept Header',\
   chain,\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'8',\
   t:none,\
   pass,\
   severity:'NOTICE',\
   id:920311,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_ACCEPT'"
     SecRule REQUEST_METHOD "!^OPTIONS$" \
       "chain"
          SecRule &REQUEST_HEADERS:User-Agent "@eq 0" \
            "t:none,\
            setvar:'tx.msg=%{rule.msg}',\
            setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
            setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"


#
# Empty User-Agent Header
#
# -=[ Rule Logic ]=-
# This rules will check to see if the User-Agent header is empty.
#
# Note that there is a second rule, 920320, which will check for
# the existence of the User-Agent header.
#

SecRule REQUEST_HEADERS:User-Agent "^$" \
  "msg:'Empty User Agent Header',\
   severity:'NOTICE',\
   phase:request,\
   t:none,\
   pass,\
   id:920330,\
   rev:'1',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EMPTY_HEADER_UA',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"

#
# Missing Content-Type Header with Request Body
#
# -=[ Rule Logic]=-
# This rule will first check to see if the value of the Content-Length header is
# non-equal to 0. The chained rule is then checking the existence of the
# Content-Type header. The RFCs do not state there must be a
# Content-Type header. However, a request missing a Content-Header is a
# strong indication of a non-compliant browser.
#
# -=[ References ]=-
# http://httpwg.org/specs/rfc7231.html#header.content-type

SecRule REQUEST_HEADERS:Content-Length "!^0$" \
  "msg:'Request Containing Content, but Missing Content-Type header',\
   chain,\
   phase:request,\
   rev:'3',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   t:none,\
   block,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   id:920340,\
   severity:'NOTICE'"
     SecRule &REQUEST_HEADERS:Content-Type "@eq 0" \
       "t:none,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"

# Check that the host header is not an IP address
# This is not an HTTP RFC violation but it is indicative of automated client access.
# Many web-based worms propagate by scanning IP address blocks.
#
# -=[ Rule Logic ]=-
# This rule triggers if the Host header contains all digits (and possible port)
#
# -=[ References ]=-
# http://technet.microsoft.com/en-us/magazine/2005.01.hackerbasher.aspx
#

SecRule REQUEST_HEADERS:Host "^[\d.:]+$" \
  "msg:'Host header is a numeric IP address',\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   t:none,\
   block,\
   logdata:'%{matched_var}',\
   severity:'WARNING',\
   id:920350,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/IP_HOST',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/6.5.10',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/POLICY/IP_HOST-%{matched_var_name}=%{matched_var}"


# In most cases, you should expect a certain volume of each a request on your
# website. For example, a request with 400 arguments, can be suspicious.
# This file creates limitations on the request.
#
# TODO Look at the rules in this file, and define the sizes you'd like to enforce.
#      Note that most of the rules are commented out by default.
#      Uncomment the rules you need
#


#
# Maximum number of arguments in request limited
#
SecRule &TX:MAX_NUM_ARGS "@eq 1" \
  "chain,\
   phase:request,\
   t:none,\
   block,\
   msg:'Too many arguments in request',\
   id:920380,\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/SIZE_LIMIT'"
     SecRule &ARGS "@gt %{tx.max_num_args}" \
       "t:none,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/POLICY/SIZE_LIMIT-%{matched_var_name}=%{matched_var}"

## -- Arguments limits --
#
# Limit argument name length
#
SecRule &TX:ARG_NAME_LENGTH "@eq 1" \
  "chain,\
   phase:request,\
   t:none,\
   block,\
   msg:'Argument name too long',\
   id:920360,\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/SIZE_LIMIT'"
     SecRule ARGS_NAMES "@gt %{tx.arg_name_length}" \
       "t:none,\
        t:length,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/POLICY/SIZE_LIMIT-%{matched_var_name}=%{matched_var}"

#
# Limit argument value length
#
SecRule &TX:ARG_LENGTH "@eq 1" \
  "chain,\
   phase:request,\
   t:none,\
   block,\
   msg:'Argument value too long',\
   id:920370,\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/SIZE_LIMIT'"
     SecRule ARGS "@gt %{tx.arg_length}" \
       "t:none,\
        t:length,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/POLICY/SIZE_LIMIT-%{matched_var_name}=%{matched_var}"

#
# Limit arguments total length
#
SecRule &TX:TOTAL_ARG_LENGTH "@eq 1" \
  "chain,\
   phase:request,\
   t:none,\
   block,\
   msg:'Total arguments size exceeded',\
   id:920390,\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/SIZE_LIMIT'"
     SecRule ARGS_COMBINED_SIZE "@gt %{tx.total_arg_length}" \
       "t:none,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/POLICY/SIZE_LIMIT-%{matched_var_name}=%{matched_var}"


#
# -- File upload limits --
#
# Individual file size is limited
SecRule &TX:MAX_FILE_SIZE "@eq 1" \
  "chain,\
   phase:request,\
   t:none,\
   block,\
   msg:'Uploaded file size too large',\
   id:920400,\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/SIZE_LIMIT'"
     SecRule REQUEST_HEADERS:Content-Type "@beginsWith multipart/form-data" \
       "chain"
         SecRule REQUEST_HEADERS:Content-Length "@gt %{tx.max_file_size}" \
           "t:none,\
            setvar:'tx.msg=%{rule.msg}',\
            setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
            setvar:tx.%{rule.id}-OWASP_CRS/POLICY/SIZE_LIMIT-%{matched_var_name}=%{matched_var}"

#
# Combined file size is limited
#
SecRule &TX:COMBINED_FILE_SIZES "@eq 1" \
  "chain,\
   phase:request,\
   t:none,\
   block,\
   msg:'Total uploaded files size too large',\
   id:920410,\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/SIZE_LIMIT'"
     SecRule FILES_COMBINED_SIZE "@gt %{tx.combined_file_sizes}" \
       "t:none,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/POLICY/SIZE_LIMIT-%{matched_var_name}=%{matched_var}"



#
# Restrict which content-types we accept.
#
SecRule REQUEST_METHOD "!^(?:GET|HEAD|PROPFIND|OPTIONS)$" \
  "phase:request,\
   chain,\
   t:none,\
   block,\
   msg:'Request content type is not allowed by policy',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   id:920420,\
   severity:'CRITICAL',\
   logdata:'%{matched_var}',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/ENCODING_NOT_ALLOWED',\
   tag:'WASCTC/WASC-20',\
   tag:'OWASP_TOP_10/A1',\
   tag:'OWASP_AppSensor/EE2',\
   tag:'PCI/12.1'"
     SecRule REQUEST_HEADERS:Content-Type "^([^;\s]+)" \
       "chain,\
        capture"
          SecRule TX:0 "!^%{tx.allowed_request_content_type}$" \
            "t:none,\
             ctl:forceRequestBodyVariable=On,\
             setvar:'tx.msg=%{rule.msg}',\
             setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
             setvar:tx.%{rule.id}-OWASP_CRS/POLICY/CONTENT_TYPE_NOT_ALLOWED-%{matched_var_name}=%{matched_var}"

#
# Restrict protocol versions.
#
SecRule REQUEST_PROTOCOL "!@within %{tx.allowed_http_versions}" \
  "phase:request,\
   t:none,\
   block,\
   msg:'HTTP protocol version is not allowed by policy',\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   id:920430,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/PROTOCOL_NOT_ALLOWED',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A6',\
   tag:'PCI/6.5.10',\
   logdata:'%{matched_var}',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/POLICY/PROTOCOL_NOT_ALLOWED-%{matched_var_name}=%{matched_var}"

#
# Restrict file extension
#
SecRule REQUEST_BASENAME "\.(.*)$" \
  "chain,\
   capture,\
   phase:request,\
   t:none,t:urlDecodeUni,t:lowercase,\
   block,\
   msg:'URL file extension is restricted by policy',\
   severity:'CRITICAL',\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   id:920440,\
   logdata:'%{TX.0}',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/EXT_RESTRICTED',\
   tag:'WASCTC/WASC-15',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/6.5.10',logdata:'%{TX.0}',\
   setvar:tx.extension=.%{tx.1}/"
     SecRule TX:EXTENSION "@within %{tx.restricted_extensions}" \
       "t:none,\
        setvar:'tx.msg=%{rule.msg}',\
        setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
        setvar:tx.%{rule.id}-OWASP_CRS/POLICY/EXT_RESTRICTED-%{matched_var_name}=%{matched_var}"

#
# Restricted HTTP headers
#
# -=[ Rule Logic ]=-
# The use of certain headers is restricted. They are listed in the variable
# TX.restricted_headers.
#
# The headers are transformed into lowercase before the match.  In order to
# make sure that only complete header names are matching, the names in
# TX.restricted_headers are wrapped in slashes. This guarantees that the
# header Range (-> /range/) is not matching the restricted header
# /content-range/ for example.
#
# This is a chained rule, where the first rule fills a set of variables of the
# form TX.header_name_<HEADER_NAME>. The second rule is then executed for all
# variables of the form TX.header_name_<HEADER_NAME>.
#
# As a consequence of the construction of the rule, the alert message and the
# alert data will not display the original header name Content-Range, but
# /content-range/ instead.
#
#
# -=[ References ]=-
# https://access.redhat.com/security/vulnerabilities/httpoxy (Header Proxy)
#
SecRule REQUEST_HEADERS_NAMES "@rx ^(.*)$" \
  "msg:'HTTP header is restricted by policy (%{MATCHED_VAR})',\
   severity:'CRITICAL',\
   phase:request,\
   t:none,\
   block,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   id:920450,\
   capture,\
   logdata:' Restricted header detected: %{matched_var}',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/POLICY/HEADER_RESTRICTED',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/12.1',\
   tag:'WASCTC/WASC-15',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/12.1',\
   t:lowercase,\
   setvar:'tx.header_name_%{tx.0}=/%{tx.0}/',\
   chain"
     SecRule TX:/^HEADER_NAME_/ "@within %{tx.restricted_headers}" \
   	"setvar:'tx.msg=%{rule.msg}',\
   	 setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   	 setvar:'tx.%{rule.id}-OWASP_CRS/POLICY/HEADERS_RESTRICTED-%{matched_var_name}=%{matched_var}'"


SecRule TX:PARANOIA_LEVEL "@lt 2" "phase:1,id:920013,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
SecRule TX:PARANOIA_LEVEL "@lt 2" "phase:2,id:920014,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
#
# -= Paranoia Level 2 =- (apply only when tx.paranoia_level is sufficiently high: 2 or higher)
#

#
# -=[ Rule Logic ]=-
#
# Check the number of range fields in the Range request header.
#
# An excessive number of Range request headers can be used to DoS a server.
# The original CVE proposed an arbitrary upper limit of 5 range fields.
#
# Several clients are known to request PDF fields with up to 34 range
# fields. Therefore the standard rule does not cover PDF files. This is
# performed in two separate (stricter) siblings of this rule.
#
# 920200: PL2: Limit of 5 range header fields for all filenames outside of PDFs
# 920201: PL2: Limit of 34 range header fields for PDFs
# 920202: PL4: Limit of 5 range header fields for PDFs
#
# -=[ References ]=-
# https://httpd.apache.org/security/CVE-2011-3192.txt

SecRule REQUEST_HEADERS:Range|REQUEST_HEADERS:Request-Range "^bytes=((\d+)?\-(\d+)?\s*,?\s*){6}" \
  "phase:request,\
   capture,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'Range: Too many fields (6 or more)',\
   logdata:'%{matched_var}',\
   severity:'WARNING',\
   id:920200,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
   tag:'paranoia-level/2',\
   chain"
   SecRule REQUEST_BASENAME "!@endsWith .pdf" \
   	"setvar:'tx.msg=%{rule.msg}',\
	 setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
	 setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}"

#
# This is a sibling of rule 920200
#

SecRule REQUEST_BASENAME "@endsWith .pdf" \
  "phase:request,\
   capture,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'Range: Too many fields for pdf request (35 or more)',\
   logdata:'%{matched_var}',\
   severity:'WARNING',\
   id:920201,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
   tag:'paranoia-level/2',\
   chain"
   SecRule REQUEST_HEADERS:Range|REQUEST_HEADERS:Request-Range "^bytes=((\d+)?\-(\d+)?\s*,?\s*){35}" \
   	   "setvar:'tx.msg=%{rule.msg}',\
	   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
	   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}"


SecRule ARGS "\%((?!$|\W)|[0-9a-fA-F]{2}|u[0-9a-fA-F]{4})" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'Multiple URL Encoding Detected',\
   id:920230,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   tag:'paranoia-level/2',\
   severity:'WARNING',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


#
# Missing Accept Header
#
# -=[ Rule Logic ]=-
# This rule generates a notice if the Accept header is missing.
#
SecRule &REQUEST_HEADERS:Accept "@eq 0" \
  "msg:'Request Missing an Accept Header',\
   chain,\
   phase:request,\
   rev:'3',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'8',\
   t:none,\
   pass,\
   severity:'NOTICE',\
   id:920300,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_ACCEPT',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/6.5.10',\
   tag:'paranoia-level/2'"
     SecRule REQUEST_METHOD "!^OPTIONS$" \
       "chain"
	  SecRule REQUEST_HEADERS:User-Agent "!@pm AppleWebKit Android" \
	    "t:none,\
            setvar:'tx.msg=%{rule.msg}',\
            setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
            setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"

#
# PL2: This is a stricter sibling of 920270.
#
SecRule REQUEST_URI|REQUEST_HEADERS|ARGS|ARGS_NAMES "@validateByteRange 9,10,13,32-126,128-255" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   block,\
   msg:'Invalid character in request (non printable characters)',\
   id:920271,\
   severity:'CRITICAL',\
   t:none,t:urlDecodeUni,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   tag:'paranoia-level/2',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


#
# Missing User-Agent Header
#
# -=[ Rule Logic ]=-
# This rules will check to see if there is a User-Agent header or not.
#

SecRule &REQUEST_HEADERS:User-Agent "@eq 0" \
  "msg:'Missing User Agent Header',\
   severity:'NOTICE',\
   phase:request,\
   rev:'1',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   t:none,\
   pass,\
   id:920320,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_UA',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/6.5.10',\
   tag:'paranoia-level/2',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.notice_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER-%{matched_var_name}=%{matched_var}"


#
# PL2: This is a stricter sibling of 920120.
#
SecRule FILES_NAMES|FILES "['\";=]" \
  "msg:'Attempted multipart/form-data bypass',\
  severity:'CRITICAL',\
  id:920121,\
  ver:'OWASP_CRS/3.0.0',\
  rev:'1',\
  maturity:'9',\
  accuracy:'7',\
  logdata:'%{matched_var}',\
  phase:request,\
  block,\
  t:none,t:urlDecodeUni,\
  tag:'application-multi',\
  tag:'language-multi',\
  tag:'platform-multi',\
  tag:'attack-protocol',\
  tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ',\
  tag:'CAPEC-272',\
  tag:'paranoia-level/2',\
  setvar:'tx.msg=%{rule.msg}',\
  setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
  setvar:'tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_REQ-%{matched_var_name}=%{matched_var}'"


SecRule TX:PARANOIA_LEVEL "@lt 3" "phase:1,id:920015,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
SecRule TX:PARANOIA_LEVEL "@lt 3" "phase:2,id:920016,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
#
# -= Paranoia Level 3 =- (apply only when tx.paranoia_level is sufficiently high: 3 or higher)
#

#
# PL 3: This is a stricter sibling of 920270. Ascii range: Printable characters in the low range
#
SecRule REQUEST_URI|REQUEST_HEADERS|ARGS|ARGS_NAMES|REQUEST_BODY "@validateByteRange 32-36,38-126" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   block,\
   msg:'Invalid character in request (outside of printable chars below ascii 127)',\
   id:920272,\
   severity:'CRITICAL',\
   t:none,t:urlDecodeUni,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   tag:'paranoia-level/3',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"



SecRule TX:PARANOIA_LEVEL "@lt 4" "phase:1,id:920017,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
SecRule TX:PARANOIA_LEVEL "@lt 4" "phase:2,id:920018,nolog,pass,skipAfter:END-REQUEST-920-PROTOCOL-ENFORCEMENT"
#
# -= Paranoia Level 4 =- (apply only when tx.paranoia_level is sufficiently high: 4 or higher)
#

#
# This is a stricter sibling of rule 920200
#

SecRule REQUEST_BASENAME "@endsWith .pdf" \
  "phase:request,\
   capture,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'6',\
   accuracy:'8',\
   t:none,\
   block,\
   msg:'Range: Too many fields for pdf request (6 or more)',\
   logdata:'%{matched_var}',\
   severity:'WARNING',\
   id:920202,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ',\
   tag:'paranoia-level/4',\
   chain"
   SecRule REQUEST_HEADERS:Range|REQUEST_HEADERS:Request-Range "^bytes=((\d+)?\-(\d+)?\s*,?\s*){6}" \
   	   "setvar:'tx.msg=%{rule.msg}',\
	   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
	   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/INVALID_HREQ-%{matched_var_name}=%{matched_var}"


#
# This is a stricter sibling of 920270.
#
SecRule ARGS|ARGS_NAMES|REQUEST_BODY "@validateByteRange 38,44-46,48-58,61,65-90,95,97-122" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   block,\
   msg:'Invalid character in request (outside of very strict set)',\
   id:920273,\
   severity:'CRITICAL',\
   t:none,t:urlDecodeUni,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   tag:'paranoia-level/4',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"

#
# This is a stricter sibling of 920270.
#
SecRule REQUEST_HEADERS|!REQUEST_HEADERS:User-Agent|!REQUEST_HEADERS:Referer|!REQUEST_HEADERS:Cookie "@validateByteRange 32,34,38,42-59,61,65-90,95,97-122" \
  "phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   block,\
   msg:'Invalid character in request headers (outside of very strict set)',\
   id:920274,\
   severity:'CRITICAL',\
   t:none,t:urlDecodeUni,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/EVASION',\
   tag:'paranoia-level/4',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/PROTOCOL_VIOLATION/EVASION-%{matched_var_name}=%{matched_var}"


# -=[ Abnormal Character Escapes ]=-
#
# [ Rule Logic ]
# Consider the following payload: arg=cat+/e\tc/pa\ssw\d
# Here, \s and \d were only used to obfuscate the string passwd and a lot of
# parsers will silently ignore the non-necessary escapes. The case with \t is
# a bit different though, as \t is a natural escape for the TAB character,
# so we will avoid this (and \n, \r, etc.).
#
# This rule aims to detect non-necessary, abnormal esacpes. You could say it is
# a nice # way to forbid the backslash character where it is not needed.
#
# This is a new rule at paranoia level 4. We expect quite a few false positives
# for this rule and we will later evaluate if the rule makes any sense at all.
# The rule is redundant with 920273 and 920274 in PL4. But if the rule proofs
# to be useful and false positives remain at a reasonable level, then it might
# be shifted to PL3 in a future release, where it would be the only rule
# covering the backslash escape.
#
# The rule construct is overly complex due to the fact that matching the
# backslash character with \b did not work. \Q\\\E does match the backslash
# character though. This is thus the base of the rule. We forbid the backslash
# when followed by a list of basic ascii characters - unless the backslash
# is preceded by another backslash character, which is being checked via a
# negative look-behind construct. If that is the case, the backslash character
# is allowed.
#
SecRule REQUEST_URI|REQUEST_HEADERS|ARGS|ARGS_NAMES "(?<!\Q\\\E)\Q\\\E[cdeghijklmpqwxyz123456789]" \
  "phase:request,\
   id:920460,\
   rev:'1',\
   accuracy:'1',\
   maturity:'1',\
   ver:'OWASP_CRS/3.0.0',\
   block,\
   log,\
   severity:'CRITICAL',\
   capture,\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'paranoia-level/4',\
   t:none,t:urlDecodeUni,t:htmlEntityDecode,t:lowercase,\
   ctl:auditLogParts=+E,\
   logdata:'Matched Data: %{TX.0} found within %{MATCHED_VAR_NAME}: %{MATCHED_VAR}',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:'tx.http_violation_score=+%{tx.critical_anomaly_score}',\
   setvar:tx.anomaly_score=+%{tx.critical_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/WEB_ATTACK/ABNORMAL-ESCAPE-%{matched_var_name}=%{matched_var}"


#
# -= Paranoia Levels Finished =-
#
SecMarker "END-REQUEST-920-PROTOCOL-ENFORCEMENT"