CVE-2013-2099: Canonical Ubuntu Linux

Medium severity, CVSS 4.3. EPSS: 4.9% chance of exploitation in the next 30 days.

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: version 12.04 only; version 12.10 only; version 13.04 only
• Python Python: version 3.2.0 only; version 3.2.1 only; version 3.2.2 only; version 3.2.3 only; version 3.2.4 only; version 3.2.5 only; …

Published 2013-10-09. Last modified 2026-06-16.