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# Bad password
## GSSAPI - NTLM
```python
import gssapi
import os
import tempfile
ntlm = gssapi.OID.from_int_seq('1.3.6.1.4.1.311.2.2.10')
with tempfile.NamedTemporaryFile() as temp_fd:
with open(temp_fd.name, mode='wb') as fd:
fd.write(b'DOMAIN:USER:PASS')
os.environ['NTLM_USER_FILE'] = temp_fd.name
c_cred = gssapi.raw.acquire_cred_with_password(gssapi.Name('USER@DOMAIN', name_type=gssapi.NameType.user),
b'invalid', usage='initiate', mechs=[ntlm]).creds
s_cred = gssapi.Credentials(usage='accept', mechs=[ntlm])
c = gssapi.SecurityContext(name=gssapi.Name('http@test', name_type=gssapi.NameType.hostbased_service),
creds=c_cred, mech=ntlm, usage='initiate')
s = gssapi.SecurityContext(creds=s_cred, usage='accept')
auth = c.step(s.step(c.step()))
s.step(auth)
```
Outputs
```
# Kerberos 5 release 1.17 - gssnlmtssp 0.7.0
gssapi.raw.misc.GSSError: Major (851968): Unspecified GSS failure. Minor code may provide more information, Minor (22): Invalid argument
```
_Note: Heimdal isn't used for NTLM because you cannot use acquire_cred_with_password._
# NTLM - Invalid MIC
```python
import gssapi
import os
import tempfile
ntlm = gssapi.OID.from_int_seq('1.3.6.1.4.1.311.2.2.10')
with tempfile.NamedTemporaryFile() as temp_fd:
with open(temp_fd.name, mode='wb') as fd:
fd.write(b'DOMAIN:USER:PASS')
os.environ['NTLM_USER_FILE'] = temp_fd.name
c_cred = gssapi.Credentials(usage='initiate', mechs=[ntlm])
s_cred = gssapi.Credentials(usage='accept', mechs=[ntlm])
c = gssapi.SecurityContext(name=gssapi.Name('http@test', name_type=gssapi.NameType.hostbased_service),
creds=c_cred, mech=ntlm, usage='initiate')
s = gssapi.SecurityContext(creds=s_cred, usage='accept')
require_mic = gssapi.OID.from_int_seq('1.3.6.1.4.1.7165.655.1.2')
nego = c.step()
# Setting this here tells the client to set the MIC.
gssapi.raw.inquire_sec_context_by_oid(c, require_mic)
challenge = s.step(nego)
auth = c.step(challenge)
# Manually change the MIC to an invalid value
auth = auth[:64] + (b"\x11" * 16) + auth[80:]
s.step(auth)
```
Outputs
```
# Kerberos 5 release 1.17 - gssnlmtssp 0.7.0
gssapi.raw.exceptions.InvalidTokenError: Major (589824): Invalid token was supplied, Minor (13): Permission denied
```
_Note: Heimdal uses NTLMv1 auth which does not use a MIC, another reason why we don't use that for auth._
# Bad Channel Bindings
## GSSAPI - Kerberos
```python
import gssapi
import socket
from gssapi.raw import ChannelBindings
kerberos = gssapi.OID.from_int_seq('1.2.840.113554.1.2.2')
cbt1 = ChannelBindings(application_data=b"\x01")
cbt2 = ChannelBindings(application_data=b"\x02")
username = gssapi.Name('admin@DOMAIN.LOCAL', name_type=gssapi.NameType.user)
c_cred = gssapi.raw.acquire_cred_with_password(username, b'password', usage='initiate', mechs=[kerberos]).creds
s_cred = gssapi.Credentials(usage='accept', mechs=[kerberos])
c = gssapi.SecurityContext(name=gssapi.Name('host@%s' % socket.gethostname(), name_type=gssapi.NameType.hostbased_service),
creds=c_cred, mech=kerberos, usage='initiate', channel_bindings=cbt1)
s = gssapi.SecurityContext(creds=s_cred, usage='accept', channel_bindings=cbt2)
token1 = c.step()
token2 = s.step(token1) # Heimdal fails here
c.step(token2) # MIT KRB5 fails here
```
Outputs
```
# Kerberos 5 release 1.17
gssapi.raw.misc.GSSError: Major (851968): Unspecified GSS failure. Minor code may provide more information, Minor (2529638972): Generic error (see e-text)
# heimdal 7.7.0
gssapi.raw.exceptions.BadChannelBindingsError: Major (262144): Incorrect channel bindings were supplied, Minor (0): Success
```
## GSSAPI - NTLM
```python
import gssapi
import os
import tempfile
from gssapi.raw import ChannelBindings
ntlm = gssapi.OID.from_int_seq('1.3.6.1.4.1.311.2.2.10')
cbt1 = ChannelBindings(application_data=b"\x01")
cbt2 = ChannelBindings(application_data=b"\x02")
with tempfile.NamedTemporaryFile() as temp_fd:
with open(temp_fd.name, mode='wb') as fd:
fd.write(b'DOMAIN:USER:PASS')
os.environ['NTLM_USER_FILE'] = temp_fd.name
c_cred = gssapi.Credentials(usage='initiate', mechs=[ntlm])
s_cred = gssapi.Credentials(usage='accept', mechs=[ntlm])
c = gssapi.SecurityContext(name=gssapi.Name('http@test', name_type=gssapi.NameType.hostbased_service),
creds=c_cred, mech=ntlm, usage='initiate', channel_bindings=cbt1)
s = gssapi.SecurityContext(creds=s_cred, usage='accept', channel_bindings=cbt2)
nego = c.step()
challenge = s.step(nego)
auth = c.step(challenge)
s.step(auth)
```
Outputs
```
# Kerberos 5 release 1.17 - gssnlmtssp 0.7.0
gssapi.raw.exceptions.InvalidTokenError: Major (589824): Invalid token was supplied, Minor (13): Permission denied
```
## SSPI - Kerberos
```python
```
## SSPI - NTLM
```python
```
# Kerberos no mutual auth
By setting a flags and not with `mutual_authentication`, `c.step(token2)` will fail.
```python
import gssapi
import socket
kerberos = gssapi.OID.from_int_seq('1.2.840.113554.1.2.2')
username = gssapi.Name('admin@DOMAIN.LOCAL', name_type=gssapi.NameType.user)
c_cred = gssapi.raw.acquire_cred_with_password(username, b'password', usage='initiate', mechs=[kerberos]).creds
s_cred = gssapi.Credentials(usage='accept', mechs=[kerberos])
c = gssapi.SecurityContext(name=gssapi.Name('host@%s' % socket.gethostname(), name_type=gssapi.NameType.hostbased_service),
creds=c_cred, mech=kerberos, usage='initiate', flags=gssapi.RequirementFlag.integrity)
s = gssapi.SecurityContext(creds=s_cred, usage='accept')
token1 = c.step()
token2 = s.step(token1)
c.step(token2)
```
Outputs
```
# Kerberos 5 release 1.17
gssapi.raw.misc.GSSError: Major (851968): Unspecified GSS failure. Minor code may provide more information, Minor (39756036): Context is already fully established
# heimdal 7.7.0
gssapi.raw.exceptions.MalformedParameterError: Major (51183616): A parameter was malformed Miscellaneous failure (see text), Minor (0): Success
```
|
