CVE-2026-100785: Vulnerability in Mozilla Firefox
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the DOM: Core & HTML component of Mozilla Firefox, which could potentially allow an attacker to cause memory corruption. The issue was resolved in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The Mozilla advisory lists this vulnerability among multiple high-impact security fixes released on September 29, 2026. No active exploitation has been reported.
Potential Impact
The vulnerability is rated as high impact by Mozilla due to the use-after-free nature, which can lead to memory corruption and potentially arbitrary code execution or browser instability. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official update.
CVE-2026-100785: Vulnerability in Mozilla Firefox
Description
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
CVSS v3.1
Score 8.8high
Affected software
Mozilla
Firefox
pkg:github/mozilla/firefoxRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the DOM: Core & HTML component of Mozilla Firefox, which could potentially allow an attacker to cause memory corruption. The issue was resolved in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The Mozilla advisory lists this vulnerability among multiple high-impact security fixes released on September 29, 2026. No active exploitation has been reported.
Potential Impact
The vulnerability is rated as high impact by Mozilla due to the use-after-free nature, which can lead to memory corruption and potentially arbitrary code execution or browser instability. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:17:05.689Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-98/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","vendor":"Mozilla"}]
Threat ID: 6abbb3eff7a7c54106640982
Added to database: 09/29/2026, 12:49:51 UTC
Last enriched: 09/29/2026, 13:18:54 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 3
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