CVE-2011-1521: Python

Medium severity, CVSS 6.4. EPSS: 3.6% chance of exploitation in the next 30 days.

The urllib and urllib2 modules in Python 2.x before 2.7.2 and 3.x before 3.2.1 process Location headers that specify redirection to file: URLs, which makes it easier for remote attackers to obtain sensitive information or cause a denial of service (resource consumption) via a crafted URL, as demonstrated by the file:///etc/passwd and file:///dev/zero URLs.

Affected products

• Python Python: version 2.0 only; version 2.0.1 only; version 2.1 only; version 2.1.1 only; version 2.1.2 only; version 2.1.3 only; …

Published 2011-05-24. Last modified 2026-06-16.