CVE-2026-96512

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.

Overview

State: PUBLISHED
Assigner (CNA): redhat
CVSS severity: HIGH
CVSS score: 7.8 / 10
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Effective score: 7.8 / 10 HIGH source: CNA overview
CWE(s): CWE-863
Reserved: 2026-09-23
Published: 2026-09-23 13:22 UTC
Last updated: 2026-09-24 03:55 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/96xxx/CVE-2026-96512.json
Linked Threat: CVE-2026-96512 — Sudo: sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-23 14:17:10 UTC
NVD last modified: 2026-09-24 04:18:04 UTC
NVD CVSS v3.1: 7.8 / 10 HIGH source: secalert@redhat.com
NVD CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Exploitability subscore: 1.8 / 10
Impact subscore: 5.9 / 10

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-85290
Assigner: redhat
Published: Sep 23, 2026, 1:22:33 PM
Updated: Sep 24, 2026, 3:55:22 AM
EUVD base score (CVSS 3.1): 7.8 / 10
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EUVD-reported EPSS: 0.0000
Aliases: GHSA-jj2h-hcrf-9gfx

ENISA 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.

EUVD references (3)

Affected products (5)

Vendor	Product	Versions	Platforms
Red Hat	Red Hat Enterprise Linux 10	—	—
Red Hat	Red Hat Enterprise Linux 7	—	—
Red Hat	Red Hat Enterprise Linux 8	—	—
Red Hat	Red Hat Enterprise Linux 9	—	—
Red Hat	Red Hat Hardened Images	—	—

Vendor references (3)

References embedded in the original CVE record by the assigning CNA.

https://access.redhat.com/security/cve/CVE-2026-96512 vdb-entryx_refsource_REDHAT
RHBZ#2539327 issue-trackingx_refsource_REDHAT
https://github.com/sudo-project/sudo/commit/1820a349687522f51023d1ae5925125f59679a8c

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (3)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://access.redhat.com/security/cve/CVE-2026-96512 secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2539327 secalert@redhat.com
https://github.com/sudo-project/sudo/commit/1820a349687522f51023d1ae5925125f59679a8c secalert@redhat.com

Remediations (10)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Security Updates - Red Hat Customer Portal

web:access.redhat.com

Products & tools Red Hat Documentation Find answers, get guidance, and learn how to use Red Hat products. Red Hat Ecosystem Catalog Find hardware, software, and cloud providers―and download container images―certified to perform with Red Hat technologies.

2026-09-24 11:07 UTC
Security Advisory - Action Required - Active Exploitation of CVE-2026 ...

web:blog.checkpoint.com

CVE - 2026 -93616 is a newly discovered zero-day vulnerability in Security Management, and a fix is available now as part of this advisory. Fixes are available for both vulnerabilities. Customers running affected versions should install the applicable fixes immediately. Affected versions and remediation instructions are detailed below.

2026-09-24 11:07 UTC
CVE-2026-96512: Red Hat Incorrect Authorization | CVETodo

web:cvetodo.com

CVE-2026-96512 is a CVSS 7.8 high-severity vulnerability in Red Hat products. Includes technical details, affected versions, and mitigation steps.

2026-09-24 11:07 UTC
Security Update Guide - Microsoft

web:msrc.microsoft.com

The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.

2026-09-24 11:07 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-24 11:07 UTC
Portal for ArcGIS Security 2026 Update 2 Patch - Esri Support

web:support.esri.com

This patch deals specifically with the issues listed below under Issues Addressed with this Patch . As part of the patch installation, the Portal for ArcGIS service is stopped and restarted. The restart may take several minutes depending on the number of items on the enterprise deployment. As a best practice, clear the browser cache and re-launch the browser after installing the patch . This ...

2026-09-24 11:07 UTC
Critical Patches Issued for Microsoft Products, July 14, 2026

web:www.cisecurity.org

Microsoft reports CVE - 2026 -56164 has been exploited in the wild. CVE - 2026 -56164 may allow remote cyber threat actors to gain unauthorized access to on-premises SharePoint Server instances. Microsoft noted that integrating its Antimalware Scan Interface (AMSI) can provide temporary mitigation by actively scanning and detecting malicious POST requests associated with exploitation attempts. The ...

2026-09-24 11:07 UTC
August's Patch Tuesday is a monster: 751 fixes, with an exploited ...

web:www.computerworld.com

August's Patch Tuesday is a big one: 751 fixes, an exploited WinSock flaw and plenty of critical Windows, Office and Exchange issues.

2026-09-24 11:07 UTC
CVE-2026-96512: Red Hat: A flaw was found in sudo - Rapid7

web:www.rapid7.com

CVE-2026-96512 : Red Hat: A flaw was found in sudo. View severity, references, and remediation details from Rapid7.

2026-09-24 11:07 UTC
Patch Tuesday September 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-09-24 11:07 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-96512.json.

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