From ceaa1bfd91d55fba01fa48988aacb90e032ec3d0 Mon Sep 17 00:00:00 2001 From: Remi Collet Date: Mon, 15 Nov 2021 11:39:00 +0100 Subject: Fix #79971 special character is breaking the path in xml function CVE-2021-21707 --- php-bug79971.patch | 208 +++++++++++++++++++++++++++++++++++++++++++++++++++++ php.spec | 8 ++- 2 files changed, 215 insertions(+), 1 deletion(-) create mode 100644 php-bug79971.patch diff --git a/php-bug79971.patch b/php-bug79971.patch new file mode 100644 index 0000000..28e7889 --- /dev/null +++ b/php-bug79971.patch @@ -0,0 +1,208 @@ +From 9e9a4876bb9cafe4d4ef20a469ffd4124d8f0ef1 Mon Sep 17 00:00:00 2001 +From: "Christoph M. Becker" +Date: Tue, 1 Sep 2020 10:04:28 +0200 +Subject: [PATCH 1/3] Fix #79971: special character is breaking the path in xml + function + +The libxml based XML functions accepting a filename actually accept +URIs with possibly percent-encoded characters. Percent-encoded NUL +bytes lead to truncation, like non-encoded NUL bytes would. We catch +those, and let the functions fail with a respective warning. + +(cherry picked from commit f15f8fc573eb38c3c73e23e0930063a6f6409ed4) +--- + ext/dom/domimplementation.c | 5 +++++ + ext/dom/tests/bug79971_2.phpt | 20 ++++++++++++++++++++ + ext/libxml/libxml.c | 9 +++++++++ + ext/simplexml/tests/bug79971_1.phpt | 27 +++++++++++++++++++++++++++ + ext/simplexml/tests/bug79971_1.xml | 2 ++ + 5 files changed, 63 insertions(+) + create mode 100644 ext/dom/tests/bug79971_2.phpt + create mode 100644 ext/simplexml/tests/bug79971_1.phpt + create mode 100644 ext/simplexml/tests/bug79971_1.xml + +diff --git a/ext/dom/domimplementation.c b/ext/dom/domimplementation.c +index ee050e21fd..486a49d52b 100644 +--- a/ext/dom/domimplementation.c ++++ b/ext/dom/domimplementation.c +@@ -114,6 +114,11 @@ PHP_METHOD(domimplementation, createDocumentType) + pch2 = (xmlChar *) systemid; + } + ++ if (strstr(name, "%00")) { ++ php_error_docref(NULL, E_WARNING, "URI must not contain percent-encoded NUL bytes"); ++ RETURN_FALSE; ++ } ++ + uri = xmlParseURI(name); + if (uri != NULL && uri->opaque != NULL) { + localname = xmlStrdup((xmlChar *) uri->opaque); +diff --git a/ext/dom/tests/bug79971_2.phpt b/ext/dom/tests/bug79971_2.phpt +new file mode 100644 +index 0000000000..c4e6b1e4e0 +--- /dev/null ++++ b/ext/dom/tests/bug79971_2.phpt +@@ -0,0 +1,20 @@ ++--TEST-- ++Bug #79971 (special character is breaking the path in xml function) ++--SKIPIF-- ++ ++--FILE-- ++createDocumentType("$uri%00foo")); ++?> ++--EXPECTF-- ++Warning: DOMImplementation::createDocumentType(): URI must not contain percent-encoded NUL bytes in %s on line %d ++bool(false) +diff --git a/ext/libxml/libxml.c b/ext/libxml/libxml.c +index da30004f36..f481353683 100644 +--- a/ext/libxml/libxml.c ++++ b/ext/libxml/libxml.c +@@ -308,6 +308,10 @@ static void *php_libxml_streams_IO_open_wrapper(const char *filename, const char + int isescaped=0; + xmlURI *uri; + ++ if (strstr(filename, "%00")) { ++ php_error_docref(NULL, E_WARNING, "URI must not contain percent-encoded NUL bytes"); ++ return NULL; ++ } + + uri = xmlParseURI(filename); + if (uri && (uri->scheme == NULL || +@@ -438,6 +442,11 @@ php_libxml_output_buffer_create_filename(const char *URI, + if (URI == NULL) + return(NULL); + ++ if (strstr(URI, "%00")) { ++ php_error_docref(NULL, E_WARNING, "URI must not contain percent-encoded NUL bytes"); ++ return NULL; ++ } ++ + puri = xmlParseURI(URI); + if (puri != NULL) { + if (puri->scheme != NULL) +diff --git a/ext/simplexml/tests/bug79971_1.phpt b/ext/simplexml/tests/bug79971_1.phpt +new file mode 100644 +index 0000000000..197776d82d +--- /dev/null ++++ b/ext/simplexml/tests/bug79971_1.phpt +@@ -0,0 +1,27 @@ ++--TEST-- ++Bug #79971 (special character is breaking the path in xml function) ++--SKIPIF-- ++ ++--FILE-- ++asXML("$uri.out%00foo")); ++?> ++--EXPECTF-- ++Warning: simplexml_load_file(): URI must not contain percent-encoded NUL bytes in %s on line %d ++ ++Warning: simplexml_load_file(): I/O warning : failed to load external entity "%s/bug79971_1.xml%00foo" in %s on line %d ++bool(false) ++ ++Warning: SimpleXMLElement::asXML(): URI must not contain percent-encoded NUL bytes in %s on line %d ++bool(false) +diff --git a/ext/simplexml/tests/bug79971_1.xml b/ext/simplexml/tests/bug79971_1.xml +new file mode 100644 +index 0000000000..912bb76d9d +--- /dev/null ++++ b/ext/simplexml/tests/bug79971_1.xml +@@ -0,0 +1,2 @@ ++ ++ +-- +2.31.1 + +From 927082f30d8bfb1434df25494e804bdc3d13ca5b Mon Sep 17 00:00:00 2001 +From: Remi Collet +Date: Mon, 15 Nov 2021 09:05:33 +0100 +Subject: [PATCH 2/3] NEWS + +(cherry picked from commit c032381da0bfb6457aa9cfa7a430790f6eab8178) +--- + NEWS | 8 +++++++- + 1 file changed, 7 insertions(+), 1 deletion(-) + +diff --git a/NEWS b/NEWS +index fe2c75f2cf..0207f4caed 100644 +--- a/NEWS ++++ b/NEWS +@@ -1,7 +1,13 @@ + PHP NEWS + ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| + +-Backported from 7.4.25 ++Backported from 7.3.33 ++ ++- XML: ++ . Fix #79971: special character is breaking the path in xml function. ++ (CVE-2021-21707) (cmb) ++ ++Backported from 7.3.32 + + - FPM: + . Fixed bug #81026 (PHP-FPM oob R/W in root process leading to privilege +-- +2.31.1 + +From 271e8b9203ba752de436cb090e3fe8f27c792de4 Mon Sep 17 00:00:00 2001 +From: Remi Collet +Date: Mon, 15 Nov 2021 09:57:10 +0100 +Subject: [PATCH 3/3] fix new tests + +(cherry picked from commit b21524ff3db15da5a7779cba73e3774eb5404d40) +--- + ext/dom/tests/bug79971_2.phpt | 2 +- + ext/simplexml/tests/bug79971_1.phpt | 2 +- + 2 files changed, 2 insertions(+), 2 deletions(-) + +diff --git a/ext/dom/tests/bug79971_2.phpt b/ext/dom/tests/bug79971_2.phpt +index c4e6b1e4e0..01cd123541 100644 +--- a/ext/dom/tests/bug79971_2.phpt ++++ b/ext/dom/tests/bug79971_2.phpt +@@ -7,7 +7,7 @@ if (!extension_loaded('dom')) die('skip dom extension not available'); + --FILE-- + + --FILE-- + - 7.0.33-32 +- Fix #79971 special character is breaking the path in xml function + CVE-2021-21707 + * Wed Oct 20 2021 Remi Collet - 7.0.33-31 - fix PHP-FPM oob R/W in root process leading to priv escalation CVE-2021-21703 -- cgit