CVE-2011-0491: Tor

Medium severity, CVSS 5.0. EPSS: 2.5% chance of exploitation in the next 30 days.

The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."

Affected products

• Tor Tor: up to and including 0.2.1.28; version 0.0.2 only; version 0.0.2_pre13 only; version 0.0.2_pre14 only; version 0.0.2_pre15 only; version 0.0.2_pre16 only; …

Published 2011-01-19. Last modified 2026-06-16.