From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mail.openembedded.org (Postfix) with ESMTP id 82A6678E4C for ; Wed, 24 Oct 2018 16:02:08 +0000 (UTC) Received: from sinanubuntu1604.mkjiurmyylmellclgttazegk5f.bx.internal.cloudapp.net (unknown [13.68.205.212]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 46309205F4; Wed, 24 Oct 2018 16:02:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540396929; bh=16KlTglIH86LiVHrgdrX8GiVvyyfEPpJoTTeLYKsZVw=; h=From:To:Cc:Subject:Date:From; b=e7pJPyCc4sXRQCs3W4DRURv8fc3V799oB5eSEdnvHSmOz3tnBP2wT82AlpG1xfAUP yIPUbwQIMKewZz9x7zjzUQXEc0jj6Od3xGG7FRBfG0C0lo8CvBG9+FPbMvJGxoUQRi fZYtAzVHFfXiYAJPUL4H13fTPWCN3I0QXOR8Lpbw= From: Sinan Kaya To: openembedded-core@lists.openembedded.org Date: Wed, 24 Oct 2018 16:02:06 +0000 Message-Id: <20181024160207.13429-1-okaya@kernel.org> X-Mailer: git-send-email 2.19.0 MIME-Version: 1.0 Subject: [sumo] [PATCH v1] python: CVE-2018-1061 X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Oct 2018 16:02:08 -0000 Content-Transfer-Encoding: 8bit * CVE-2018-1060 Prevent low-grade poplib REDOS: The regex to test a mail server's timestamp is susceptible to catastrophic backtracking on long evil responses from the server. Happily, the maximum length of malicious inputs is 2K thanks to a limit introduced in the fix for CVE-2013-1752. * CVE-2018-1061 Prevent difflib REDOS The default regex for IS_LINE_JUNK is susceptible to catastrophic backtracking. This is a potential DOS vector. Replace it with an equivalent non-vulnerable regex. Affects = 2.7 CVE: CVE-2018-1060 CVE: CVE-2018-1061 Ref: https://access.redhat.com/security/cve/cve-2018-1060 Ref: https://access.redhat.com/security/cve/cve-2018-1061 Signed-off-by: Sinan Kaya --- .../python/python/CVE-2018-1061.patch | 162 ++++++++++++++++++ meta/recipes-devtools/python/python_2.7.14.bb | 1 + 2 files changed, 163 insertions(+) create mode 100644 meta/recipes-devtools/python/python/CVE-2018-1061.patch diff --git a/meta/recipes-devtools/python/python/CVE-2018-1061.patch b/meta/recipes-devtools/python/python/CVE-2018-1061.patch new file mode 100644 index 0000000000..d16b8e9185 --- /dev/null +++ b/meta/recipes-devtools/python/python/CVE-2018-1061.patch @@ -0,0 +1,162 @@ +From ee518362805f7f30d4fb11e784ada1e8f4167af9 Mon Sep 17 00:00:00 2001 +From: Benjamin Peterson +Date: Sat, 3 Mar 2018 22:18:17 -0800 +Subject: [PATCH] [2.7] bpo-32981: Fix catastrophic backtracking vulns + (GH-5955) + +* Prevent low-grade poplib REDOS (CVE-2018-1060) + +The regex to test a mail server's timestamp is susceptible to +catastrophic backtracking on long evil responses from the server. + +Happily, the maximum length of malicious inputs is 2K thanks +to a limit introduced in the fix for CVE-2013-1752. + +A 2KB evil response from the mail server would result in small slowdowns +(milliseconds vs. microseconds) accumulated over many apop calls. +This is a potential DOS vector via accumulated slowdowns. + +Replace it with a similar non-vulnerable regex. + +The new regex is RFC compliant. +The old regex was non-compliant in edge cases. + +* Prevent difflib REDOS (CVE-2018-1061) + +The default regex for IS_LINE_JUNK is susceptible to +catastrophic backtracking. +This is a potential DOS vector. + +Replace it with an equivalent non-vulnerable regex. + +Also introduce unit and REDOS tests for difflib. + +Co-authored-by: Tim Peters +Co-authored-by: Christian Heimes . +(cherry picked from commit 0e6c8ee2358a2e23117501826c008842acb835ac) +Signed-off-by: Sinan Kaya +CVE: CVE-2018-1061 +Upstream-Status: Backport [https://github.com/python/cpython/commit/e052d40cea15f582b50947f7d906b39744dc62a2] +Signed-off-by: Sinan Kaya +--- + Lib/difflib.py | 2 +- + Lib/poplib.py | 2 +- + Lib/test/test_difflib.py | 22 ++++++++++++++++++- + Lib/test/test_poplib.py | 10 +++++++++ + Misc/ACKS | 2 ++ + .../2018-03-02-10-24-52.bpo-32981.O_qDyj.rst | 4 ++++ + 6 files changed, 39 insertions(+), 3 deletions(-) + create mode 100644 Misc/NEWS.d/next/Security/2018-03-02-10-24-52.bpo-32981.O_qDyj.rst + +diff --git a/Lib/difflib.py b/Lib/difflib.py +index 1c6fbdbedc..788a92df3f 100644 +--- a/Lib/difflib.py ++++ b/Lib/difflib.py +@@ -1103,7 +1103,7 @@ class Differ: + + import re + +-def IS_LINE_JUNK(line, pat=re.compile(r"\s*#?\s*$").match): ++def IS_LINE_JUNK(line, pat=re.compile(r"\s*(?:#\s*)?$").match): + r""" + Return 1 for ignorable line: iff `line` is blank or contains a single '#'. + +diff --git a/Lib/poplib.py b/Lib/poplib.py +index b91e5f72d2..a238510b38 100644 +--- a/Lib/poplib.py ++++ b/Lib/poplib.py +@@ -274,7 +274,7 @@ class POP3: + return self._shortcmd('RPOP %s' % user) + + +- timestamp = re.compile(r'\+OK.*(<[^>]+>)') ++ timestamp = re.compile(br'\+OK.[^<]*(<.*>)') + + def apop(self, user, secret): + """Authorisation +diff --git a/Lib/test/test_difflib.py b/Lib/test/test_difflib.py +index 35f2c36ca7..d8277b79b8 100644 +--- a/Lib/test/test_difflib.py ++++ b/Lib/test/test_difflib.py +@@ -269,13 +269,33 @@ class TestOutputFormat(unittest.TestCase): + self.assertEqual(fmt(3,6), '4,6') + self.assertEqual(fmt(0,0), '0') + ++class TestJunkAPIs(unittest.TestCase): ++ def test_is_line_junk_true(self): ++ for line in ['#', ' ', ' #', '# ', ' # ', '']: ++ self.assertTrue(difflib.IS_LINE_JUNK(line), repr(line)) ++ ++ def test_is_line_junk_false(self): ++ for line in ['##', ' ##', '## ', 'abc ', 'abc #', 'Mr. Moose is up!']: ++ self.assertFalse(difflib.IS_LINE_JUNK(line), repr(line)) ++ ++ def test_is_line_junk_REDOS(self): ++ evil_input = ('\t' * 1000000) + '##' ++ self.assertFalse(difflib.IS_LINE_JUNK(evil_input)) ++ ++ def test_is_character_junk_true(self): ++ for char in [' ', '\t']: ++ self.assertTrue(difflib.IS_CHARACTER_JUNK(char), repr(char)) ++ ++ def test_is_character_junk_false(self): ++ for char in ['a', '#', '\n', '\f', '\r', '\v']: ++ self.assertFalse(difflib.IS_CHARACTER_JUNK(char), repr(char)) + + def test_main(): + difflib.HtmlDiff._default_prefix = 0 + Doctests = doctest.DocTestSuite(difflib) + run_unittest( + TestWithAscii, TestAutojunk, TestSFpatches, TestSFbugs, +- TestOutputFormat, Doctests) ++ TestOutputFormat, TestJunkAPIs) + + if __name__ == '__main__': + test_main() +diff --git a/Lib/test/test_poplib.py b/Lib/test/test_poplib.py +index 23d688724b..d2143759ba 100644 +--- a/Lib/test/test_poplib.py ++++ b/Lib/test/test_poplib.py +@@ -211,6 +211,16 @@ class TestPOP3Class(TestCase): + def test_rpop(self): + self.assertOK(self.client.rpop('foo')) + ++ def test_apop_REDOS(self): ++ # Replace welcome with very long evil welcome. ++ # NB The upper bound on welcome length is currently 2048. ++ # At this length, evil input makes each apop call take ++ # on the order of milliseconds instead of microseconds. ++ evil_welcome = b'+OK' + (b'<' * 1000000) ++ with test_support.swap_attr(self.client, 'welcome', evil_welcome): ++ # The evil welcome is invalid, so apop should throw. ++ self.assertRaises(poplib.error_proto, self.client.apop, 'a', 'kb') ++ + def test_top(self): + expected = ('+OK 116 bytes', + ['From: postmaster@python.org', 'Content-Type: text/plain', +diff --git a/Misc/ACKS b/Misc/ACKS +index 229a874ffc..ef3c08557f 100644 +--- a/Misc/ACKS ++++ b/Misc/ACKS +@@ -316,6 +316,8 @@ Kushal Das + Jonathan Dasteel + Pierre-Yves David + A. Jesse Jiryu Davis ++Jamie (James C.) Davis ++Ratnadeep Debnath + Merlijn van Deen + John DeGood + Ned Deily +diff --git a/Misc/NEWS.d/next/Security/2018-03-02-10-24-52.bpo-32981.O_qDyj.rst b/Misc/NEWS.d/next/Security/2018-03-02-10-24-52.bpo-32981.O_qDyj.rst +new file mode 100644 +index 0000000000..9ebabb44f9 +--- /dev/null ++++ b/Misc/NEWS.d/next/Security/2018-03-02-10-24-52.bpo-32981.O_qDyj.rst +@@ -0,0 +1,4 @@ ++Regexes in difflib and poplib were vulnerable to catastrophic backtracking. ++These regexes formed potential DOS vectors (REDOS). They have been ++refactored. This resolves CVE-2018-1060 and CVE-2018-1061. ++Patch by Jamie Davis. +-- +2.19.0 + diff --git a/meta/recipes-devtools/python/python_2.7.14.bb b/meta/recipes-devtools/python/python_2.7.14.bb index b923b9237b..6986b484bd 100644 --- a/meta/recipes-devtools/python/python_2.7.14.bb +++ b/meta/recipes-devtools/python/python_2.7.14.bb @@ -31,6 +31,7 @@ SRC_URI += "\ file://pass-missing-libraries-to-Extension-for-mul.patch \ file://support_SOURCE_DATE_EPOCH_in_py_compile_2.7.patch \ file://fix-gc-alignment.patch \ + file://CVE-2018-1061.patch \ " S = "${WORKDIR}/Python-${PV}" -- 2.19.0