You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
111 lines
5.0 KiB
111 lines
5.0 KiB
From c660debb97f4f422255a82fef2d77804552c043a Mon Sep 17 00:00:00 2001 |
|
From: Christian Heimes <christian@python.org> |
|
Date: Tue, 15 Jan 2019 18:16:30 +0100 |
|
Subject: [PATCH] bpo-35746: Fix segfault in ssl's cert parser |
|
|
|
CVE-2019-5010, Fix a NULL pointer deref in ssl module. The cert parser did |
|
not handle CRL distribution points with empty DP or URI correctly. A |
|
malicious or buggy certificate can result into segfault. |
|
|
|
Signed-off-by: Christian Heimes <christian@python.org> |
|
--- |
|
Lib/test/talos-2019-0758.pem | 22 +++++++++++++++++++ |
|
Lib/test/test_ssl.py | 22 +++++++++++++++++++ |
|
.../2019-01-15-18-16-05.bpo-35746.nMSd0j.rst | 3 +++ |
|
Modules/_ssl.c | 4 ++++ |
|
4 files changed, 51 insertions(+) |
|
create mode 100644 Lib/test/talos-2019-0758.pem |
|
create mode 100644 Misc/NEWS.d/next/Security/2019-01-15-18-16-05.bpo-35746.nMSd0j.rst |
|
|
|
diff --git a/Lib/test/talos-2019-0758.pem b/Lib/test/talos-2019-0758.pem |
|
new file mode 100644 |
|
index 000000000000..13b95a77fd8a |
|
--- /dev/null |
|
+++ b/Lib/test/talos-2019-0758.pem |
|
@@ -0,0 +1,22 @@ |
|
+-----BEGIN CERTIFICATE----- |
|
+MIIDqDCCApKgAwIBAgIBAjALBgkqhkiG9w0BAQswHzELMAkGA1UEBhMCVUsxEDAO |
|
+BgNVBAMTB2NvZHktY2EwHhcNMTgwNjE4MTgwMDU4WhcNMjgwNjE0MTgwMDU4WjA7 |
|
+MQswCQYDVQQGEwJVSzEsMCoGA1UEAxMjY29kZW5vbWljb24tdm0tMi50ZXN0Lmxh |
|
+bC5jaXNjby5jb20wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQC63fGB |
|
+J80A9Av1GB0bptslKRIUtJm8EeEu34HkDWbL6AJY0P8WfDtlXjlPaLqFa6sqH6ES |
|
+V48prSm1ZUbDSVL8R6BYVYpOlK8/48xk4pGTgRzv69gf5SGtQLwHy8UPBKgjSZoD |
|
+5a5k5wJXGswhKFFNqyyxqCvWmMnJWxXTt2XDCiWc4g4YAWi4O4+6SeeHVAV9rV7C |
|
+1wxqjzKovVe2uZOHjKEzJbbIU6JBPb6TRfMdRdYOw98n1VXDcKVgdX2DuuqjCzHP |
|
+WhU4Tw050M9NaK3eXp4Mh69VuiKoBGOLSOcS8reqHIU46Reg0hqeL8LIL6OhFHIF |
|
+j7HR6V1X6F+BfRS/AgMBAAGjgdYwgdMwCQYDVR0TBAIwADAdBgNVHQ4EFgQUOktp |
|
+HQjxDXXUg8prleY9jeLKeQ4wTwYDVR0jBEgwRoAUx6zgPygZ0ZErF9sPC4+5e2Io |
|
+UU+hI6QhMB8xCzAJBgNVBAYTAlVLMRAwDgYDVQQDEwdjb2R5LWNhggkA1QEAuwb7 |
|
+2s0wCQYDVR0SBAIwADAuBgNVHREEJzAlgiNjb2Rlbm9taWNvbi12bS0yLnRlc3Qu |
|
+bGFsLmNpc2NvLmNvbTAOBgNVHQ8BAf8EBAMCBaAwCwYDVR0fBAQwAjAAMAsGCSqG |
|
+SIb3DQEBCwOCAQEAvqantx2yBlM11RoFiCfi+AfSblXPdrIrHvccepV4pYc/yO6p |
|
+t1f2dxHQb8rWH3i6cWag/EgIZx+HJQvo0rgPY1BFJsX1WnYf1/znZpkUBGbVmlJr |
|
+t/dW1gSkNS6sPsM0Q+7HPgEv8CPDNK5eo7vU2seE0iWOkxSyVUuiCEY9ZVGaLVit |
|
+p0C78nZ35Pdv4I+1cosmHl28+es1WI22rrnmdBpH8J1eY6WvUw2xuZHLeNVN0TzV |
|
+Q3qq53AaCWuLOD1AjESWuUCxMZTK9DPS4JKXTK8RLyDeqOvJGjsSWp3kL0y3GaQ+ |
|
+10T1rfkKJub2+m9A9duin1fn6tHc2wSvB7m3DA== |
|
+-----END CERTIFICATE----- |
|
diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py |
|
index 7f6b93148f45..1fc657f4d867 100644 |
|
--- a/Lib/test/test_ssl.py |
|
+++ b/Lib/test/test_ssl.py |
|
@@ -115,6 +115,7 @@ def data_file(*name): |
|
BADKEY = data_file("badkey.pem") |
|
NOKIACERT = data_file("nokia.pem") |
|
NULLBYTECERT = data_file("nullbytecert.pem") |
|
+TALOS_INVALID_CRLDP = data_file("talos-2019-0758.pem") |
|
|
|
DHFILE = data_file("ffdh3072.pem") |
|
BYTES_DHFILE = os.fsencode(DHFILE) |
|
@@ -348,6 +349,27 @@ def test_parse_cert(self): |
|
self.assertEqual(p['crlDistributionPoints'], |
|
('http://SVRIntl-G3-crl.verisign.com/SVRIntlG3.crl',)) |
|
|
|
+ def test_parse_cert_CVE_2019_5010(self): |
|
+ p = ssl._ssl._test_decode_cert(TALOS_INVALID_CRLDP) |
|
+ if support.verbose: |
|
+ sys.stdout.write("\n" + pprint.pformat(p) + "\n") |
|
+ self.assertEqual( |
|
+ p, |
|
+ { |
|
+ 'issuer': ( |
|
+ (('countryName', 'UK'),), (('commonName', 'cody-ca'),)), |
|
+ 'notAfter': 'Jun 14 18:00:58 2028 GMT', |
|
+ 'notBefore': 'Jun 18 18:00:58 2018 GMT', |
|
+ 'serialNumber': '02', |
|
+ 'subject': ((('countryName', 'UK'),), |
|
+ (('commonName', |
|
+ 'codenomicon-vm-2.test.lal.cisco.com'),)), |
|
+ 'subjectAltName': ( |
|
+ ('DNS', 'codenomicon-vm-2.test.lal.cisco.com'),), |
|
+ 'version': 3 |
|
+ } |
|
+ ) |
|
+ |
|
def test_parse_cert_CVE_2013_4238(self): |
|
p = ssl._ssl._test_decode_cert(NULLBYTECERT) |
|
if support.verbose: |
|
diff --git a/Misc/NEWS.d/next/Security/2019-01-15-18-16-05.bpo-35746.nMSd0j.rst b/Misc/NEWS.d/next/Security/2019-01-15-18-16-05.bpo-35746.nMSd0j.rst |
|
new file mode 100644 |
|
index 000000000000..dffe347eec84 |
|
--- /dev/null |
|
+++ b/Misc/NEWS.d/next/Security/2019-01-15-18-16-05.bpo-35746.nMSd0j.rst |
|
@@ -0,0 +1,3 @@ |
|
+[CVE-2019-5010] Fix a NULL pointer deref in ssl module. The cert parser did |
|
+not handle CRL distribution points with empty DP or URI correctly. A |
|
+malicious or buggy certificate can result into segfault. |
|
diff --git a/Modules/_ssl.c b/Modules/_ssl.c |
|
index 4e3352d9e661..0e720e268d93 100644 |
|
--- a/Modules/_ssl.c |
|
+++ b/Modules/_ssl.c |
|
@@ -1515,6 +1515,10 @@ _get_crl_dp(X509 *certificate) { |
|
STACK_OF(GENERAL_NAME) *gns; |
|
|
|
dp = sk_DIST_POINT_value(dps, i); |
|
+ if (dp->distpoint == NULL) { |
|
+ /* Ignore empty DP value, CVE-2019-5010 */ |
|
+ continue; |
|
+ } |
|
gns = dp->distpoint->name.fullname; |
|
|
|
for (j=0; j < sk_GENERAL_NAME_num(gns); j++) {
|
|
|