CVE-2013-7040: Apple Mac OS X

Medium severity, CVSS 4.3. EPSS: 3.3% chance of exploitation in the next 30 days.

Python 2.7 before 3.4 only uses the last eight bits of the prefix to randomize hash values, which causes it to compute hash values without restricting the ability to trigger hash collisions predictably and makes it easier for context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table. NOTE: this vulnerability exists because of an incomplete fix for CVE-2012-1150.

Affected products

• Apple Mac OS X: up to and including 10.10.4
• Python Python: version 2.7.1 only; version 2.7.2 only; version 2.7.3 only; version 2.7.4 only; version 2.7.5 only; version 2.7.6 only; …

Published 2014-05-19. Last modified 2026-06-17.