CVE-2013-7440

Severity: medium (CVSS 5.9 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-06-07 · updated 2026-06-17
Weakness: CWE-19

Description

The ssl.match_hostname function in CPython (aka Python) before 2.7.9 and 3.x before 3.3.3 does not properly handle wildcards in hostnames, which might allow man-in-the-middle attackers to spoof servers via a crafted certificate.

Affected products

Python: through 2.7.8; 3.0, 3.0.1, 3.1, 3.1.1, 3.1.2, 3.1.3 (+19)

References

http://seclists.org/oss-sec/2015/q2/483
http://seclists.org/oss-sec/2015/q2/523
http://www.securityfocus.com/bid/74707
https://access.redhat.com/errata/RHSA-2016:1166
https://bugs.python.org/issue17997
https://bugzilla.redhat.com/show_bug.cgi?id=1224999
https://hg.python.org/cpython/rev/10d0edadbcdd
http://seclists.org/oss-sec/2015/q2/483
http://seclists.org/oss-sec/2015/q2/523
http://www.securityfocus.com/bid/74707
https://access.redhat.com/errata/RHSA-2016:1166
https://bugs.python.org/issue17997

Get alerted when CVE-2013-7440 or the next vulnerability affects your stack