CVE-2026-8957

Description

Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Overview

State: PUBLISHED
Assigner (CNA): mozilla
CVSS severity: high
CVSS score: 8.8 / 10
CVSS vector: AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Effective score: 8.8 / 10 HIGH source: CNA overview
CWE(s): —
Reserved: 2026-05-19
Published: 2026-05-19 12:29 UTC
Last updated: 2026-05-20 15:37 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8957.json
Linked Threat: CVE-2026-8957 — CVE-2026-8957

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: 2026-05-19 14:16:52 UTC
NVD last modified: 2026-05-20 17:16:30 UTC
NVD CVSS v3.1: 8.8 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Exploitability subscore: 2.8 / 10
Impact subscore: 5.9 / 10
EPSS score: 0.0004 (probability of exploitation in next 30 days)
EPSS percentile: 12.43% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

NVD-assigned CWE(s): CWE-269 (differs from the CNA list above)

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-2026-30908
Assigner: mozilla
Published: May 19, 2026, 12:29:52 PM
Updated: May 20, 2026, 3:37:58 PM
EUVD base score (CVSS 3.1): 8.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EUVD-reported EPSS: 0.0400
Aliases: GHSA-83v4-m9qr-xgp9

ENISA description: Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

EUVD references (5)

Affected products (2)

Vendor	Product	Versions	Platforms
Mozilla	Firefox	`140.11` (unaffected), `151` (unaffected)	—
Mozilla	Thunderbird	`140.11` (unaffected), `151` (unaffected)	—

Affected products — CPE 2.3 (4) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

Vendor references (5)

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

Web references (14)

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

http://www.mozilla.org/security/announce/2026/mfsa2026-51.html rapid7:www.mozilla.org
http://www.mozilla.org/security/announce/2026/mfsa2026-48.html rapid7:www.mozilla.org
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-30908 rapid7:euvd.enisa.europa.eu
http://cwe.mitre.org/data/definitions/269.html rapid7:cwe.mitre.org
https://attackerkb.com/topics/CVE-2026-8957 rapid7:attackerkb.com
http://www.mozilla.org/security/announce/2026/mfsa2026-46.html rapid7:www.mozilla.org
https://www.first.org/epss/ tenable:www.first.org
https://www.mozilla.org/security/advisories/mfsa2026-46/ tenable:www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-48/ tenable:www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-50/ tenable:www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-51/ tenable:www.mozilla.org
https://bugzilla.mozilla.org/show_bug.cgi?id=2033850 tenable:bugzilla.mozilla.org
https://nvd.nist.gov/vuln/detail/CVE-2026-8957 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-8957 tenable:www.cve.org

NVD-tagged references (5)

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://bugzilla.mozilla.org/show_bug.cgi?id=2033850 security@mozilla.org Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/ security@mozilla.org Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-48/ security@mozilla.org Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/ security@mozilla.org Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-51/ security@mozilla.org Vendor Advisory

Remediations (13)

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

CVE-2026-8957 - Vulnerability Details - OpenCVE

web:app.opencve.io

Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Upgrade Mozilla Firefox to version 151 or to Firefox ESR 140.11 or later. Upgrade Mozilla Thunderbird to version 151 or to Thunderbird ESR 140.11 or later.

2026-05-23 22:18 UTC
CVE-2026-8957 - Privilege escalation in the Enterprise Policies component

web:cvefeed.io

The following products are affected by CVE-2026-8957 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.

2026-05-23 22:18 UTC
CVE-2026-8957 - Exploits & Severity - Feedly

web:feedly.com

Impacted is an unknown function of the component Enterprise Policies . Performing a manipulation results in privilege escalation. This vulnerability is reported as CVE-2026-8957 . The attacker must have access to the local network to execute the attack. No exploit exists. Upgrading the affected component is recommended.

2026-05-23 22:18 UTC
Privilege escalation in the Enterprise Policies component...

web:github.com

Description Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.

2026-05-23 22:18 UTC
CVE-2026-8957 | Security Details | Sonatype Guide

web:guide.sonatype.com

Technical security analysis for CVE-2026-8957 . CVSS 8.1 severity. View CVSS vectors, CWE classifications, and exploit maturity ratings.

2026-05-23 22:18 UTC
Nvd - Cve-2026-8957

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-23 22:18 UTC
Addressing Exchange Server May 2026 vulnerability CVE-2026-42897

web:techcommunity.microsoft.com

We wanted to tell you how to address the Exchange Server May 2026 vulnerability CVE - 2026 -42897.

2026-05-23 22:18 UTC
CVE-2026-8957 | Ubuntu

web:ubuntu.com

Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things.

2026-05-23 22:18 UTC
CVE-2026-8957 Common Vulnerabilities and Exposures | SUSE

web:www.suse.com

Upstream information CVE-2026-8957 at MITRE Description Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

2026-05-23 22:18 UTC
CVE-2026-8957 - High Vulnerability - TheHackerWire

web:www.thehackerwire.com

How do I fix or mitigate CVE-2026-8957 ? To protect against CVE-2026-8957 , you should: (1) Apply the latest security patches from Mozilla, (2) Check official security advisories for specific remediation steps, (3) Update affected software to the latest version, and (4) Monitor your systems for any signs of exploitation.

2026-05-23 22:18 UTC
SecuriTricks - CVE-2026-8957 - 8.8/10

web:securitricks.com

CVE CVE-2026-8957 - Score : 8.8 - Source : security@mozilla.org - Description : Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

2026-05-26 02:58 UTC
Microsoft Confirms Active 0-Day Exploit—Check Emergency Mitigation

web:www.forbes.com

Updated May 17: This article, originally published May 16, has been updated to include further details on the emergency mitigation process recommended after the CVE - 2026 -42897 Microsoft Exchange ...

2026-05-26 02:58 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

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

2026-05-26 02:58 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-8957.json.

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