CVE-2009-1338: Linux Kernel

Medium severity, CVSS 4.6. EPSS: 0.4% chance of exploitation in the next 30 days.

The kill_something_info function in kernel/signal.c in the Linux kernel before 2.6.28 does not consider PID namespaces when processing signals directed to PID -1, which allows local users to bypass the intended namespace isolation, and send arbitrary signals to all processes in all namespaces, via a kill command.

Affected products

• Linux Linux Kernel: up to and including 2.6.27.21; version 2.2.27 only; version 2.4.36 only; version 2.4.36.1 only; version 2.4.36.2 only; version 2.4.36.3 only; …

Published 2009-04-22. Last modified 2026-06-16.