CVE-2026-96512
Sudo: sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization
HIGH 7.8
At a glance
- Source
- NVD
- EPSS
- EPSS 0.32 % · percentile 25 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- redhat
- NVD status
- Awaiting Analysis
Description
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.
Weaknesses (CWE)
- CWE-863 — Incorrect Authorization
References
- https://access.redhat.com/errata/RHSA-2026:71609
- https://access.redhat.com/errata/RHSA-2026:75571
- https://access.redhat.com/errata/RHSA-2026:75579
- https://access.redhat.com/errata/RHSA-2026:75580
- https://access.redhat.com/errata/RHSA-2026:82939
- https://access.redhat.com/errata/RHSA-2026:86633
- https://access.redhat.com/errata/RHSA-2026:86634
- https://access.redhat.com/errata/RHSA-2026:86635
- https://access.redhat.com/errata/RHSA-2026:87026
- https://access.redhat.com/errata/RHSA-2026:90287
- https://access.redhat.com/errata/RHSA-2026:92325
- https://access.redhat.com/errata/RHSA-2026:92349
- https://access.redhat.com/security/cve/CVE-2026-96512
- https://bugzilla.redhat.com/show_bug.cgi?id=2539327
- https://github.com/sudo-project/sudo/commit/1820a349687522f51023d1ae5925125f59679a8c
- http://www.openwall.com/lists/oss-security/2026/09/24/4
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | redhat |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · secalert@redhat.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-85290
- GCVE · GCVE-0-2026-96512
CERT-FR advisories
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
Affected products
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |