CVE-2026-96512

Sudo: sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization

High 7.8

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.

Assigner
redhat
Published
2026-09-23
Updated
2026-10-22
Reserved
2026-09-23

Scores

SourceCVSSScoreSeverityVector
redhat3.17.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses

Affected

VendorProductVersions
Red Hat Red Hat Enterprise Linux 10 0:1.9.17-10.p2.el10_2.7 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support 0:1.9.15-8.p5.el10_0.5 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 8 0:1.9.5p2-2.el8_10 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service 0:1.9.5p2-1.el8_8.4 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions 0:1.9.5p2-1.el8_8.4 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 9 0:1.9.17p2-3.el9_8.3 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 9 0:1.9.17p2-3.el9_8.3 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions 0:1.9.5p2-10.el9_4.4 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support 0:1.9.5p2-10.el9_6.4 to < * (unaffected)
others: affected
Red Hat Red Hat Hardened Images 1.9.17-16.p2.2.hum1 to < * (unaffected)
others: affected
Red Hat Red Hat Update Infrastructure 5 1791964013 to < * (unaffected)
others: affected
Red Hat Red Hat Update Infrastructure 5 1791978693 to < * (unaffected)
others: affected
Red Hat Red Hat Enterprise Linux 7
others: affected

References

Full CVE JSON record (5.2)

API · GitHub · cve.org

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