Skip to content

CVE-2026-96512 on Cyberus Linux 26.05

Aliases: CVE-2026-96512

Packages: sudo

Status: Resolved

Advisory Information

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.

Updates

2026-10-09 02:52 CEST

Metadata changes:

  • Status for package sudo: “Resolved” (2a121edd01502b06bec005d1e632a7635d2dcdc0)

(Amended on: 2026-10-09 02:53 CEST)

2026-09-24 18:53 CEST

Metadata changes:

  • Status for package sudo: “Plausible”

Comment:

This vulnerability requires non-default configuration.

Mitigation exists:

  • Any usage of NOTBEFORE and NOTAFTER rules can be suffixed with a timezone. See man 5 sudoers.

When not suffixed with a timezone, “local time” is used, and without the fix is affected by the ambient TZ environment variable.

(Amended on: 2026-09-24 19:01 CEST)

2026-09-24 18:53 CEST

Metadata changes:

  • Status for package sudo: “New”