CVE-2026-96512: Sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization
Red Hat · Red Hat Hardened Images
Vendor fix available · Affected: Red Hat Hardened Images · Exploitation: public proof of concept (unverified)
ExploitationProof of concept public
Not in CISA KEV as of catalogue 2026.11.13 (13 Nov)
- In CISA KEV: not seen
- Exploited (reported): not seen
- Scanning observed: not seen
- Proof of concept public2 public GitHub repositories (unverified), listed by PoC-in-GitHub25 Sep
- Not established: not seen
Higher than 25% of scored CVEs
DescriptionNVD
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.
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- Red Hat
- Published
- September 2026
What changed
- PoC-in-GitHub lists 2 public GitHub repositories (unverified) PoC-in-GitHub
Coverage1 article · 1 outlet
First in our coverage: SecurityOnline, 25 Sep.
- Sudo Flaw Lets Local Users Bypass Time Restricted Rules via TZSecurityOnline · first in our coverage
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