CVE-2026-43403: Linux Kernel

High severity, CVSS 8.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: nsfs: tighten permission checks for ns iteration ioctls Even privileged services should not necessarily be able to see other privileged service's namespaces so they can't leak information to each other. Use may_see_all_namespaces() helper that centralizes this policy until the nstree adapts.

Affected products

• Linux Linux Kernel: from 6.12, before 6.12.78 (fixed in 6.12.78); from 6.13, before 6.18.20 (fixed in 6.18.20); from 6.19, before 6.19.9 (fixed in 6.19.9); version 7.0 only

Published 2026-05-08. Last modified 2026-06-17.