CVE-2026-16356: Vulnerability in Mozilla Firefox
Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13.
AI Analysis
Technical Summary
CVE-2026-16356 is a use-after-free vulnerability in the Disability Access APIs component of Mozilla Firefox that enables sandbox escape. This flaw was reported by Oskar L and is classified as high impact. It was resolved in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13. The vulnerability is part of a broader set of memory safety issues fixed in these releases, some of which showed evidence of memory corruption and potential for arbitrary code execution. The vendor advisories confirm the fix availability and recommend upgrading to these versions.
Potential Impact
Successful exploitation of this use-after-free vulnerability can allow an attacker to escape the Firefox sandbox, potentially leading to arbitrary code execution on the host system. This elevates the risk level to high due to the ability to bypass security boundaries within the browser environment. No active exploitation in the wild has been reported as of the advisory date.
Mitigation Recommendations
A fix is available and has been officially released by Mozilla. Users and administrators should upgrade to Firefox 153, Firefox ESR 115.38, or Firefox ESR 140.13 to remediate this vulnerability. No additional mitigation actions are required beyond applying these updates.
CVE-2026-16356: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13.
Affected software
pkg:github/mozilla/firefox-esrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16356 is a use-after-free vulnerability in the Disability Access APIs component of Mozilla Firefox that enables sandbox escape. This flaw was reported by Oskar L and is classified as high impact. It was resolved in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13. The vulnerability is part of a broader set of memory safety issues fixed in these releases, some of which showed evidence of memory corruption and potential for arbitrary code execution. The vendor advisories confirm the fix availability and recommend upgrading to these versions.
Potential Impact
Successful exploitation of this use-after-free vulnerability can allow an attacker to escape the Firefox sandbox, potentially leading to arbitrary code execution on the host system. This elevates the risk level to high due to the ability to bypass security boundaries within the browser environment. No active exploitation in the wild has been reported as of the advisory date.
Mitigation Recommendations
A fix is available and has been officially released by Mozilla. Users and administrators should upgrade to Firefox 153, Firefox ESR 115.38, or Firefox ESR 140.13 to remediate this vulnerability. No additional mitigation actions are required beyond applying these updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:56:01.537Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-69/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-70/","vendor":"Mozilla"}]
Threat ID: 6a5f6cb92a4a8d598926242c
Added to database: 07/21/2026, 12:57:29 UTC
Last enriched: 07/21/2026, 13:43:24 UTC
Last updated: 07/21/2026, 21:18:30 UTC
Views: 5
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