CVE-2011-4838: Jruby

Medium severity, CVSS 5.0. EPSS: 4.2% chance of exploitation in the next 30 days.

JRuby before 1.6.5.1 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table.

Affected products

• Jruby Jruby: before 1.6.5.1 (fixed in 1.6.5.1)

Published 2011-12-30. Last modified 2026-06-16.