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7.8
HIGH CVSS 3.1
CVE-2026-96512
Sudo: sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization
Overview
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.

Details
INFO

Published Date :

Sept. 23, 2026, 2:17 p.m.

Last Modified :

Oct. 14, 2026, 7:17 p.m.

Remotely Exploit :

No

Source :

[email protected]
Impact
Affected Products

The following products are affected by CVE-2026-96512 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Redhat enterprise_linux
2 Redhat update_infrastructure
3 Redhat enterprise_linux
4 Redhat hardened_images
1 Ubuntu libefiboot
: Total Affected Vendor : 2 | Products : 5
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 53f830b8-0a3f-465b-8143-3b8a9948e749
CVSS 3.1 HIGH [email protected]
Solution
Update sudo to correctly handle time-based access restrictions and ignore TZ for evaluations.
  • Update the sudo package to the latest version.
  • Reconfigure sudoers rules to include the 'Z' timezone indicator.
  • Remove the TZ environment variable from sudo execution context.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-96512.

URL Resource
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/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
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-96512 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-96512 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-96512 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-96512 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    Oct. 14, 2026

    Action Type Old Value New Value
    Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
    Added Reference https://access.redhat.com/errata/RHSA-2026:82939
  • CVE Modified by [email protected]

    Oct. 05, 2026

    Action Type Old Value New Value
    Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
    Added Reference https://access.redhat.com/errata/RHSA-2026:75571
  • CVE Modified by [email protected]

    Oct. 05, 2026

    Action Type Old Value New Value
    Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
    Added Reference https://access.redhat.com/errata/RHSA-2026:75579
  • CVE Modified by [email protected]

    Oct. 05, 2026

    Action Type Old Value New Value
    Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
    Added Reference https://access.redhat.com/errata/RHSA-2026:75580
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Sep. 24, 2026

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2026/09/24/4
  • CVE Modified by [email protected]

    Sep. 24, 2026

    Action Type Old Value New Value
    Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
    Added Reference https://access.redhat.com/errata/RHSA-2026:71609
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 24, 2026

    Action Type Old Value New Value
    Removed SSVC {'id': 'CVE-2026-96512', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-23T16:18:10.918476Z'}
    Added SSVC {'id': 'CVE-2026-96512', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-23T00:00:00+00:00'}
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 23, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-96512', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-23T16:18:10.918476Z'}
  • CVE Modified by [email protected]

    Sep. 23, 2026

    Action Type Old Value New Value
    Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
  • New CVE Received by [email protected]

    Sep. 23, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-863
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96512.json">CVE-2026-96512</a>
    Added Reference https://access.redhat.com/security/cve/CVE-2026-96512
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2539327
    Added Reference https://github.com/sudo-project/sudo/commit/1820a349687522f51023d1ae5925125f59679a8c
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact