--- a/ext/xsl/php_xsl.h
+++ b/ext/xsl/php_xsl.h
@@ -32,6 +32,7 @@ extern zend_module_entry xsl_module_entr
 #include <libxslt/xsltInternals.h>
 #include <libxslt/xsltutils.h>
 #include <libxslt/transform.h>
+#include <libxslt/security.h> 
 #if HAVE_XSL_EXSLT
 #include <libexslt/exslt.h>
 #include <libexslt/exsltconfig.h>
@@ -43,6 +44,15 @@ extern zend_module_entry xsl_module_entr
 #include <libxslt/extensions.h>
 #include <libxml/xpathInternals.h>
 
+#define XSL_SECPREF_NONE 0
+#define XSL_SECPREF_READ_FILE 2
+#define XSL_SECPREF_WRITE_FILE 4
+#define XSL_SECPREF_CREATE_DIRECTORY 8
+#define XSL_SECPREF_READ_NETWORK 16
+#define XSL_SECPREF_WRITE_NETWORK 32
+/* Default == disable all write access ==  XSL_SECPREF_WRITE_NETWORK | XSL_SECPREF_CREATE_DIRECTORY | XSL_SECPREF_WRITE_FILE */
+#define XSL_SECPREF_DEFAULT 44
+
 typedef struct _xsl_object {
 	zend_object  std;
 	void *ptr;
--- a/ext/xsl/xsltprocessor.c
+++ b/ext/xsl/xsltprocessor.c
@@ -475,6 +475,9 @@ static xmlDocPtr php_xsl_apply_styleshee
 	zval *doXInclude, *member;
 	zend_object_handlers *std_hnd;
 	FILE *f;
+	int secPrefsError = 0;
+	int secPrefsValue;
+	xsltSecurityPrefsPtr secPrefs = NULL;
 
 	node = php_libxml_import_node(docp TSRMLS_CC);
 	
@@ -531,11 +534,56 @@ static xmlDocPtr php_xsl_apply_styleshee
 	}
 	efree(member);
 
-	newdocp = xsltApplyStylesheetUser(style, doc, (const char**) params,  NULL, f, ctxt);
+	
+	secPrefsValue = INI_INT("xsl.security_prefs");
+	
+	/* if securityPrefs is set to NONE, we don't have to do any checks, but otherwise... */
+	if (secPrefsValue != XSL_SECPREF_NONE) {
+		secPrefs = xsltNewSecurityPrefs(); 
+		if (secPrefsValue & XSL_SECPREF_READ_FILE ) { 
+			if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_READ_FILE, xsltSecurityForbid)) { 
+				secPrefsError = 1;
+			}
+		}
+		if (secPrefsValue & XSL_SECPREF_WRITE_FILE ) { 
+			if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_WRITE_FILE, xsltSecurityForbid)) { 
+				secPrefsError = 1;
+			}
+		}
+		if (secPrefsValue & XSL_SECPREF_CREATE_DIRECTORY ) { 
+			if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_CREATE_DIRECTORY, xsltSecurityForbid)) { 
+				secPrefsError = 1;
+			}
+		}
+		if (secPrefsValue & XSL_SECPREF_READ_NETWORK) { 
+			if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_READ_NETWORK, xsltSecurityForbid)) { 
+				secPrefsError = 1;
+			}
+		}
+		if (secPrefsValue & XSL_SECPREF_WRITE_NETWORK) { 
+			if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_WRITE_NETWORK, xsltSecurityForbid)) { 
+				secPrefsError = 1;
+			}
+		}
+	
+		if (0 != xsltSetCtxtSecurityPrefs(secPrefs, ctxt)) { 
+			secPrefsError = 1;
+		}
+	}
+	
+	if (secPrefsError == 1) {
+		php_error_docref(NULL TSRMLS_CC, E_WARNING, "Can't set libxslt security properties, not doing transformation for security reasons");
+	} else {
+		newdocp = xsltApplyStylesheetUser(style, doc, (const char**) params,  NULL, f, ctxt);
+	}
 	if (f) {
 		fclose(f);
 	}
+	
 	xsltFreeTransformContext(ctxt);
+	if (secPrefs) {
+		xsltFreeSecurityPrefs(secPrefs);
+	}
 
 	if (intern->node_list != NULL) {
 		zend_hash_destroy(intern->node_list);
--- a/ext/xsl/php_xsl.c
+++ b/ext/xsl/php_xsl.c
@@ -141,6 +141,11 @@ zend_object_value xsl_objects_new(zend_c
 }
 /* }}} */
 
+PHP_INI_BEGIN()
+//XSL_SECPREF_CREATE_DIRECTORY | XSL_SECPREF_WRITE_NETWORK | XSL_SECPREF_WRITE_FILE == 44
+PHP_INI_ENTRY("xsl.security_prefs", "44", PHP_INI_ALL, NULL)
+PHP_INI_END()
+
 /* {{{ PHP_MINIT_FUNCTION
  */
 PHP_MINIT_FUNCTION(xsl)
@@ -167,6 +172,14 @@ PHP_MINIT_FUNCTION(xsl)
 	REGISTER_LONG_CONSTANT("XSL_CLONE_NEVER",    -1,     CONST_CS | CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("XSL_CLONE_ALWAYS",    1,     CONST_CS | CONST_PERSISTENT);
 
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_NONE",             XSL_SECPREF_NONE,             CONST_CS | CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_READ_FILE",        XSL_SECPREF_READ_FILE,        CONST_CS | CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_WRITE_FILE",       XSL_SECPREF_WRITE_FILE,       CONST_CS | CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_CREATE_DIRECTORY", XSL_SECPREF_CREATE_DIRECTORY, CONST_CS | CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_READ_NETWORK",     XSL_SECPREF_READ_NETWORK,     CONST_CS | CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_WRITE_NETWORK",    XSL_SECPREF_WRITE_NETWORK,    CONST_CS | CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("XSL_SECPREF_DEFAULT",          XSL_SECPREF_DEFAULT,          CONST_CS | CONST_PERSISTENT);
+
 	REGISTER_LONG_CONSTANT("LIBXSLT_VERSION",           LIBXSLT_VERSION,            CONST_CS | CONST_PERSISTENT);
 	REGISTER_STRING_CONSTANT("LIBXSLT_DOTTED_VERSION",  LIBXSLT_DOTTED_VERSION,     CONST_CS | CONST_PERSISTENT);
 
@@ -175,6 +188,8 @@ PHP_MINIT_FUNCTION(xsl)
 	REGISTER_STRING_CONSTANT("LIBEXSLT_DOTTED_VERSION",  LIBEXSLT_DOTTED_VERSION,     CONST_CS | CONST_PERSISTENT);
 #endif
 
+    REGISTER_INI_ENTRIES();
+
 	return SUCCESS;
 }
 /* }}} */
@@ -258,6 +273,8 @@ PHP_MSHUTDOWN_FUNCTION(xsl)
 
 	xsltCleanupGlobals();
 
+	UNREGISTER_INI_ENTRIES();
+
 	return SUCCESS;
 }
 /* }}} */
--- /dev/null
+++ b/ext/xsl/tests/bug54446.phpt
@@ -0,0 +1,95 @@
+--TEST--
+Bug #54446 (Arbitrary file creation via libxslt 'output' extension)
+--SKIPIF--
+<?php
+if (!extension_loaded('xsl')) die("skip Extension XSL is required\n");
+?>
+--FILE--
+<?php
+include("prepare.inc"); 
+
+$outputfile = dirname(__FILE__)."/bug54446test.txt";
+if (file_exists($outputfile)) {
+    unlink($outputfile);
+}
+
+$sXsl = <<<EOT
+<xsl:stylesheet version="1.0"
+	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+	xmlns:sax="http://icl.com/saxon"
+	extension-element-prefixes="sax">
+
+	<xsl:template match="/">
+		<sax:output href="$outputfile" method="text">
+			<xsl:value-of select="'0wn3d via PHP and libxslt ...'"/>
+		</sax:output>
+	</xsl:template>
+
+</xsl:stylesheet>
+EOT;
+
+$xsl->loadXML( $sXsl );
+
+# START XSLT 
+$proc->importStylesheet( $xsl ); 
+
+# TRASNFORM & PRINT 
+print $proc->transformToXML( $dom ); 
+
+
+if (file_exists($outputfile)) {
+    print "$outputfile exists, but shouldn't!\n";
+} else {
+    print "OK, no file created\n";
+}
+
+#SET NO SECURITY PREFS
+ini_set("xsl.security_prefs", XSL_SECPREF_NONE);
+
+# TRASNFORM & PRINT 
+print $proc->transformToXML( $dom ); 
+
+
+if (file_exists($outputfile)) {
+    print "OK, file exists\n";
+} else {
+    print "$outputfile doesn't exist, but should!\n";
+}
+
+unlink($outputfile);
+
+#SET SECURITY PREFS AGAIN
+ini_set("xsl.security_prefs", XSL_SECPREF_WRITE_FILE |  XSL_SECPREF_WRITE_NETWORK | XSL_SECPREF_CREATE_DIRECTORY);
+
+# TRASNFORM & PRINT 
+print $proc->transformToXML( $dom ); 
+
+if (file_exists($outputfile)) {
+    print "$outputfile exists, but shouldn't!\n";
+} else {
+    print "OK, no file created\n";
+}
+
+
+--EXPECTF--
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %s element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): File write for %s/bug54446test.txt refused in %s on line %s
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %d element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): xsltDocumentElem: write rights for %s/bug54446test.txt denied in %s on line %d
+OK, no file created
+OK, file exists
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %s element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): File write for %s/bug54446test.txt refused in %s on line %s
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %d element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): xsltDocumentElem: write rights for %s/bug54446test.txt denied in %s on line %d
+OK, no file created
+--CREDITS--
+Christian Stocker, chregu@php.net
+
--- /dev/null
+++ b/ext/xsl/tests/bug54446_with_ini.phpt
@@ -0,0 +1,95 @@
+--TEST--
+Bug #54446 (Arbitrary file creation via libxslt 'output' extension with php.ini setting)
+--SKIPIF--
+<?php
+if (!extension_loaded('xsl')) die("skip Extension XSL is required\n");
+?>
+--FILE--
+<?php
+include("prepare.inc"); 
+
+$outputfile = dirname(__FILE__)."/bug54446test.txt";
+if (file_exists($outputfile)) {
+    unlink($outputfile);
+}
+
+$sXsl = <<<EOT
+<xsl:stylesheet version="1.0"
+	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+	xmlns:sax="http://icl.com/saxon"
+	extension-element-prefixes="sax">
+
+	<xsl:template match="/">
+		<sax:output href="$outputfile" method="text">
+			<xsl:value-of select="'0wn3d via PHP and libxslt ...'"/>
+		</sax:output>
+	</xsl:template>
+
+</xsl:stylesheet>
+EOT;
+
+$xsl->loadXML( $sXsl );
+
+# START XSLT 
+$proc->importStylesheet( $xsl ); 
+
+# TRASNFORM & PRINT 
+print $proc->transformToXML( $dom ); 
+
+
+if (file_exists($outputfile)) {
+    print "$outputfile exists, but shouldn't!\n";
+} else {
+    print "OK, no file created\n";
+}
+
+#SET NO SECURITY PREFS
+ini_set("xsl.security_prefs", XSL_SECPREF_NONE);
+
+# TRASNFORM & PRINT 
+print $proc->transformToXML( $dom ); 
+
+
+if (file_exists($outputfile)) {
+    print "OK, file exists\n";
+} else {
+    print "$outputfile doesn't exist, but should!\n";
+}
+
+unlink($outputfile);
+
+#SET SECURITY PREFS AGAIN
+ini_set("xsl.security_prefs", XSL_SECPREF_WRITE_FILE |  XSL_SECPREF_WRITE_NETWORK | XSL_SECPREF_CREATE_DIRECTORY);
+
+# TRASNFORM & PRINT 
+print $proc->transformToXML( $dom ); 
+
+if (file_exists($outputfile)) {
+    print "$outputfile exists, but shouldn't!\n";
+} else {
+    print "OK, no file created\n";
+}
+
+
+--EXPECTF--
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %s element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): File write for %s/bug54446test.txt refused in %s on line %s
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %d element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): xsltDocumentElem: write rights for %s/bug54446test.txt denied in %s on line %d
+OK, no file created
+OK, file exists
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %s element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): File write for %s/bug54446test.txt refused in %s on line %s
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %d element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): xsltDocumentElem: write rights for %s/bug54446test.txt denied in %s on line %d
+OK, no file created
+--CREDITS--
+Christian Stocker, chregu@php.net
+