🛡️ CVE-2026-8953 — firefox

🔴 CVSS 9.6 — Critical ✅ No Known Exploit CWE-416 NVD
9.6
CVSS Score
0 Low4 Medium7 High9 Critical10

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.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. A user must be tricked into taking some action. The scope is changed, meaning a successful attack can affect components beyond the vulnerable one. Rated impact: confidentiality high, integrity high, availability high.

Weakness class

CVE-2026-8953 is classified as CWE-416: Use After Free. Memory is used after being released, so its contents may already belong to something else.

Affected software

CVE-2026-8953 is recorded against 2 packages.

  • firefox (from 140.0 up to 140.11.0)
  • thunderbird (fixed in 140.11)

Timeline and source

Published on 19 May 2026 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

bugzilla.mozilla.org
www.mozilla.org
www.mozilla.org
www.mozilla.org
www.mozilla.org
www.mozilla.org

CVE-2026-8953 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity CRITICAL
CVSS Score 9.6
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CWE CWE-416
Public Exploit ✅ No
Source NVD
Published 2026-05-19
Updated 2026-08-11
Modified 2026-06-17
Fix URL N/A

Affected Packages

Software From version Fixed in
firefox 140.0 140.11.0
thunderbird — 140.11

Similar Threats

Exploit Protection

Are you running firefox?

CVE-2026-8953 carries CVSS 9.6 Critical rating. BotEraser checks your installation against this and other known CVE records, and blocks IPs associated with exploit activity.

Check My Site For CVE-2026-8953 →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.