CVE-2026-109753: Vulnerability in Mozilla Firefox
Description
Incorrect boundary conditions in the Layout component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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
The vulnerability identified as CVE-2026-109753 affects the Layout component of Mozilla Firefox due to incorrect boundary conditions. This flaw could potentially impact the rendering or processing of layout elements within the browser. Mozilla has released fixes for this vulnerability in Firefox 158, Firefox ESR 115.43, and Firefox ESR 153.5.
Potential Impact
The vulnerability could lead to unexpected behavior in the Firefox Layout component. However, there are no reports of active exploitation in the wild. The exact impact details are not specified beyond the boundary condition issue.
Mitigation Recommendations
Users and administrators should update to Firefox 158, Firefox ESR 115.43, or Firefox ESR 153.5 or later to remediate this vulnerability. These versions contain the official fixes from Mozilla.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:57.847Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-107/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","vendor":"Mozilla"}]
Threat ID: 6ace2c4d2cdf04f65661d555
Added to database: 10/13/2026, 13:04:13 UTC
Last enriched: 10/13/2026, 13:34:48 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 4
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.