Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-3964
Advisory Released Date: 2026-10-12
Advisory Updated Date: 2026-10-12
A flaw was found in sudo. When sudoers rules use NOTBEFORE or NOTAFTER time-based access restrictions with timestamps that omit the trailing 'Z' timezone indicator, the time evaluation relies on the TZ environment variable inherited from the calling user. Because sudo is a setuid-root program, an unprivileged local user can set TZ to an extreme timezone offset to shift the authorization window by up to approximately 25 hours, causing expired rules to be treated as valid. This allows the user to execute commands outside the intended time window. Authentication is not bypassed; only the time-based authorization check is affected. (CVE-2026-96512)
Affected Packages:
sudo
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 sudo or yum update --advisory ALAS2-2026-3964 to update your system.
aarch64:
sudo-1.8.23-10.amzn2.3.9.aarch64
sudo-devel-1.8.23-10.amzn2.3.9.aarch64
sudo-debuginfo-1.8.23-10.amzn2.3.9.aarch64
i686:
sudo-1.8.23-10.amzn2.3.9.i686
sudo-devel-1.8.23-10.amzn2.3.9.i686
sudo-debuginfo-1.8.23-10.amzn2.3.9.i686
src:
sudo-1.8.23-10.amzn2.3.9.src
x86_64:
sudo-1.8.23-10.amzn2.3.9.x86_64
sudo-devel-1.8.23-10.amzn2.3.9.x86_64
sudo-debuginfo-1.8.23-10.amzn2.3.9.x86_64