CVE-2013-2099

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2013-10-09 · updated 2026-06-16
Weakness: CWE-399

Description

Algorithmic complexity vulnerability in the ssl.match_hostname function in Python 3.2.x, 3.3.x, and earlier, and unspecified versions of python-backports-ssl_match_hostname as used for older Python versions, allows remote attackers to cause a denial of service (CPU consumption) via multiple wildcard characters in the common name in a certificate.

Affected products

Canonical Ubuntu Linux: 12.04, 12.10, 13.04
Python: 3.2.0, 3.2.1, 3.2.2, 3.2.3, 3.2.4, 3.2.5 (+3)

References

http://bugs.python.org/issue17980
http://rhn.redhat.com/errata/RHSA-2014-1690.html
http://secunia.com/advisories/55107
http://secunia.com/advisories/55116
http://www.openwall.com/lists/oss-security/2013/05/16/6
http://www.ubuntu.com/usn/USN-1983-1
http://www.ubuntu.com/usn/USN-1984-1
http://www.ubuntu.com/usn/USN-1985-1
https://access.redhat.com/errata/RHSA-2016:1166
https://bugzilla.redhat.com/show_bug.cgi?id=963260
http://bugs.python.org/issue17980
http://rhn.redhat.com/errata/RHSA-2014-1690.html

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