CVE-2012-2135

Severity: medium (CVSS 6.4 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2012-08-14 · updated 2026-06-16

Description

The utf-16 decoder in Python 3.1 through 3.3 does not update the aligned_end variable after calling the unicode_decode_call_errorhandler function, which allows remote attackers to obtain sensitive information (process memory) or cause a denial of service (memory corruption and crash) via unspecified vectors.

Affected products

Canonical Ubuntu Linux: 10.04, 11.04, 11.10, 12.04, 12.10
Debian Linux: 6.0
Python: from 2.7.0 before 2.7.4; from 3.2.0 before 3.2.4; from 3.3.0 before 3.3.3 — fixed in 2.7.4, 3.2.4, 3.3.3

How to fix

Upgrade to a fixed version: Python 2.7.4, 3.2.4, 3.3.3. Check the vendor advisory for mitigations.

References

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=670389
http://bugs.python.org/issue14579
http://secunia.com/advisories/51087
http://secunia.com/advisories/51089
http://www.openwall.com/lists/oss-security/2012/04/25/2
http://www.openwall.com/lists/oss-security/2012/04/25/4
http://www.ubuntu.com/usn/USN-1615-1
http://www.ubuntu.com/usn/USN-1616-1
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=670389
http://bugs.python.org/issue14579
http://secunia.com/advisories/51087
http://secunia.com/advisories/51089

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