Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-3949
Advisory Released Date: 2026-09-28
Advisory Updated Date: 2026-09-28
A TOCTOU (Time-of-Check-Time-of-Use) race condition vulnerability was found in the fixfiles script in policycoreutils. When running fixfiles relabel or fixfiles restore, the script used find and chcon commands to locate and relabel unlabeled files under /tmp and other directories. A local attacker could exploit a race window between the file discovery and the label change operation by swapping directory components with symlinks, causing chcon to follow the symlink and modify SELinux labels on arbitrary system files. This could undermine SELinux mandatory access control protections on critical files such as /etc/shadow. (CVE-2026-19079)
Affected Packages:
policycoreutils
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update policycoreutils or yum update --advisory ALAS2-2026-3949 to update your system.
aarch64:
policycoreutils-2.5-22.amzn2.0.1.aarch64
policycoreutils-debuginfo-2.5-22.amzn2.0.1.aarch64
policycoreutils-python-2.5-22.amzn2.0.1.aarch64
policycoreutils-devel-2.5-22.amzn2.0.1.aarch64
policycoreutils-sandbox-2.5-22.amzn2.0.1.aarch64
policycoreutils-newrole-2.5-22.amzn2.0.1.aarch64
policycoreutils-gui-2.5-22.amzn2.0.1.aarch64
policycoreutils-restorecond-2.5-22.amzn2.0.1.aarch64
i686:
policycoreutils-2.5-22.amzn2.0.1.i686
policycoreutils-debuginfo-2.5-22.amzn2.0.1.i686
policycoreutils-python-2.5-22.amzn2.0.1.i686
policycoreutils-devel-2.5-22.amzn2.0.1.i686
policycoreutils-sandbox-2.5-22.amzn2.0.1.i686
policycoreutils-newrole-2.5-22.amzn2.0.1.i686
policycoreutils-gui-2.5-22.amzn2.0.1.i686
policycoreutils-restorecond-2.5-22.amzn2.0.1.i686
src:
policycoreutils-2.5-22.amzn2.0.1.src
x86_64:
policycoreutils-2.5-22.amzn2.0.1.x86_64
policycoreutils-debuginfo-2.5-22.amzn2.0.1.x86_64
policycoreutils-python-2.5-22.amzn2.0.1.x86_64
policycoreutils-devel-2.5-22.amzn2.0.1.x86_64
policycoreutils-sandbox-2.5-22.amzn2.0.1.x86_64
policycoreutils-newrole-2.5-22.amzn2.0.1.x86_64
policycoreutils-gui-2.5-22.amzn2.0.1.x86_64
policycoreutils-restorecond-2.5-22.amzn2.0.1.x86_64