CVE-2026-96512 Sudo: sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization
Local attackers can bypass sudo time-based authorization restrictions by manipulating the TZ environment variable, allowing execution of commands outside intended windows.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-96512?
CVE-2026-96512 is a high-severity vulnerability in Red Hat Enterprise Linux 10, published on 23 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-863
Which versions are affected by CVE-2026-96512?
Linux distribution packages (28)
sudo AlmaLinux:10 | All versions | 1.9.17-10.p2.el10_2.7 |
sudo-python-plugin AlmaLinux:10 | All versions | 1.9.17-10.p2.el10_2.7 |
sudo AlmaLinux:8 | All versions | 1.9.5p2-2.el8_10 |
sudo AlmaLinux:9 | All versions | 1.9.17p2-3.el9_8.3 |
sudo-python-plugin AlmaLinux:9 | All versions | 1.9.17p2-3.el9_8.3 |
sudo Red Hat:enterprise_linux:10.2 | All versions | 0:1.9.17-10.p2.el10_2.7 |
sudo-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 0:1.9.17-10.p2.el10_2.7 |
sudo-debugsource Red Hat:enterprise_linux:10.2 | All versions | 0:1.9.17-10.p2.el10_2.7 |
sudo-python-plugin Red Hat:enterprise_linux:10.2 | All versions | 0:1.9.17-10.p2.el10_2.7 |
sudo-python-plugin-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 0:1.9.17-10.p2.el10_2.7 |
sudo Red Hat:enterprise_linux:8::baseos | All versions | 0:1.9.5p2-2.el8_10 |
sudo-debuginfo Red Hat:enterprise_linux:8::baseos | All versions | 0:1.9.5p2-2.el8_10 |
sudo-debugsource Red Hat:enterprise_linux:8::baseos | All versions | 0:1.9.5p2-2.el8_10 |
sudo-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo-debugsource Red Hat:enterprise_linux:9::appstream | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo-python-plugin Red Hat:enterprise_linux:9::appstream | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo-python-plugin-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo Red Hat:enterprise_linux:9::baseos | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo-debugsource Red Hat:enterprise_linux:9::baseos | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo-python-plugin-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:1.9.17p2-3.el9_8.3 |
sudo Red Hat:hummingbird:1 | All versions | 0:1.9.17-16.p2.2.hum1 |
sudo-devel Red Hat:hummingbird:1 | All versions | 0:1.9.17-16.p2.2.hum1 |
sudo-logsrvd Red Hat:hummingbird:1 | All versions | 0:1.9.17-16.p2.2.hum1 |
sudo-python-plugin Red Hat:hummingbird:1 | All versions | 0:1.9.17-16.p2.2.hum1 |
sudo Rocky Linux:10 | All versions | 0:1.9.17-10.p2.el10_2.7 |
sudo Rocky Linux:8 | All versions | 0:1.9.5p2-2.el8_10 |
sudo Rocky Linux:9 | All versions | 0:1.9.17p2-3.el9_8.3 |
How do I fix CVE-2026-96512?
Apply the vendor's patch.
Is CVE-2026-96512 being exploited?
There is no known exploitation of CVE-2026-96512 in the wild and no public exploit code.
Public exploit code: 2 proofs of concept on GitHub.
Sources
Also known as ALSA-2026:75571, ALSA-2026:75579, ALSA-2026:75580, AZL-104940, BELL-CVE-2026-96512, CLSA-2026-1791552454 and 21 more.