CVE-2026-8953

Description

Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Overview

State: PUBLISHED
Assigner (CNA): mozilla
CVSS severity: critical
CVSS score: 9.6 / 10
CVSS vector: AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Effective score: 9.6 / 10 CRITICAL source: CNA overview
CWE(s): —
Reserved: 2026-05-19
Published: 2026-05-19 12:29 UTC
Last updated: 2026-05-19 17:10 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8953.json
Linked Threat: CVE-2026-8953 — CVE-2026-8953

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 14:16:51 UTC
NVD last modified: 2026-05-19 18:45:32 UTC
NVD CVSS v3.1: 9.6 / 10 CRITICAL source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Exploitability subscore: 2.8 / 10
Impact subscore: 6.0 / 10
EPSS score: 0.0004 (probability of exploitation in next 30 days)
EPSS percentile: 13.12% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

NVD-assigned CWE(s): CWE-416 (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-2026-30901
Assigner: mozilla
Published: May 19, 2026, 12:29:46 PM
Updated: May 19, 2026, 5:10:48 PM
EUVD base score (CVSS 3.1): 9.6 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EUVD-reported EPSS: 0.0500
Aliases: GHSA-c3qv-mh67-fpxw

ENISA description: Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

EUVD references (6)

Affected products (2)

Vendor	Product	Versions	Platforms
Mozilla	Firefox	`115.36` (unaffected), `140.11` (unaffected), `151` (unaffected)	—
Mozilla	Thunderbird	`140.11` (unaffected), `151` (unaffected)	—

Affected products — CPE 2.3 (3) 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:*:*:*:*:*:*:*:*

Vendor references (6)

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

Web references (17)

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
http://www.mozilla.org/security/announce/2026/mfsa2026-47.html rapid7:www.mozilla.org
http://cwe.mitre.org/data/definitions/416.html rapid7:cwe.mitre.org
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-30901 rapid7:euvd.enisa.europa.eu
https://attackerkb.com/topics/CVE-2026-8953 rapid7:attackerkb.com
http://www.mozilla.org/security/announce/2026/mfsa2026-46.html rapid7:www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-47/ 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=2029511 tenable:bugzilla.mozilla.org
https://nvd.nist.gov/vuln/detail/CVE-2026-8953 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-8953 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org
https://www.malwarebytes.com/blog/privacy/2026/05/firefox-151-packs-big-privacy-upgrades-into-a-small-update tenable:www.malwarebytes.com
https://www.mozilla.org/security/advisories/mfsa2026-46/ tenable:www.mozilla.org

NVD-tagged references (6)

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=2029511 security@mozilla.org Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/ security@mozilla.org Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-47/ 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 (16)

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

CVE-2026-8953 - Vulnerability Details - OpenCVE

web:app.opencve.io

Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Upgrade Firefox to a fixed release, such as Fx 151 or any later ESR version (115.36, 140.11, or newer). Upgrade Thunderbird to a fixed release, such as TB 151 or any later ESR version (140.11, or newer).

2026-05-23 22:18 UTC
Microsoft Patch Tuesday February 2026 - 54 Vulnerabilities Fixed ...

web:cybersecuritynews.com

Microsoft released its February 2026 Patch Tuesday updates on February 10, addressing 54 vulnerabilities, including six zero-days across Windows, Office, Azure, and developer tools.

2026-05-23 22:18 UTC
CVE-2026-8953 | Security Details | Sonatype Guide

web:guide.sonatype.com

Technical security analysis for CVE-2026-8953 . CVSS 9.6 severity. View CVSS vectors, CWE classifications, and exploit maturity ratings.

2026-05-23 22:18 UTC
Nvd - Cve-2026-8953

web:nvd.nist.gov

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

2026-05-23 22:18 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-23 22:18 UTC
CVE-2026-8953 : Sandbox Escape Vulnerability in Firefox Accessibility ...

web:securityvulnerability.io

What is CVE-2026-8953 ? A critical vulnerability has been identified in the Disability Access APIs of Firefox, which allows a sandbox escape via a use-after-free condition.

2026-05-23 22:18 UTC
Microsoft March 2026 Patch Tuesday fixes 2 zero-days, 79 flaws

web:www.bleepingcomputer.com

Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.

2026-05-23 22:18 UTC
CVE-2026-8953 Common Vulnerabilities and Exposures | SUSE

web:www.suse.com

Secure your Linux systems from CVE-2026-8953 . Stay ahead of potential threats with the latest security updates from SUSE.

2026-05-23 22:18 UTC
CVE-2026-8953 - Critical Vulnerability - TheHackerWire

web:www.thehackerwire.com

CVE-2026-8953 is a Critical severity vulnerability (CVSS 9.6). Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR...

2026-05-23 22:18 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 .

2026-05-23 22:18 UTC
CISA gives agencies until Friday to patch critical cyber bug

web:federalnewsnetwork.com

CISA's latest emergency directive tells agencies to immediately patch critical vulnerabilities in Cisco networking devices.

2026-05-26 02:58 UTC
CVE-2026-8953 - GitHub Advisory Database

web:github.com

GitHub is where people build software. More than 150 million people use GitHub to discover, fork, and contribute to over 420 million projects.

2026-05-26 02:58 UTC
SecuriTricks - CVE-2026-8953 - 9.6/10

web:securitricks.com

CVE CVE-2026-8953 - Score : 9.6 - Source : security@mozilla.org - Description : Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

2026-05-26 02:58 UTC
CVE-2026-8953 | 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.

2026-05-26 02:58 UTC
January 2026 Patch Tuesday: Updates and Analysis | CrowdStrike

web:www.crowdstrike.com

Microsoft has released security updates for 114 vulnerabilities, including three zero-days, plus eight critical CVEs in its January 2026 Patch Tuesday rollout.

2026-05-26 02:58 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-05-26 02:58 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-8953.json.

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