CVE-2026-100769: Vulnerability in Mozilla Firefox
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
AI Analysis
Technical Summary
CVE-2026-100769 is a use-after-free vulnerability affecting the JavaScript WebAssembly component in Mozilla Firefox. Use-after-free vulnerabilities occur when a program continues to use memory after it has been freed, potentially leading to memory corruption or arbitrary code execution. This specific vulnerability was reported by Tomer Fichman and has been fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The Mozilla advisory categorizes the impact as high and provides references to the bug report 2067190. There are no indications of active exploitation in the wild.
Potential Impact
The vulnerability poses a high impact risk as use-after-free bugs can lead to memory corruption, which may be exploited to execute arbitrary code or cause a denial of service. However, no active exploitation has been reported. Successful exploitation could compromise the security of affected Firefox installations.
Mitigation Recommendations
A fix for this vulnerability is available. Users and administrators should update to Firefox ESR 153.4, Firefox 157, or Firefox ESR 140.17 or later versions to remediate this issue. No additional mitigation actions are indicated by the vendor advisory.
CVE-2026-100769: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
CVSS v3.1
Score 8.8high
Affected software
Mozilla
Firefox
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-100769 is a use-after-free vulnerability affecting the JavaScript WebAssembly component in Mozilla Firefox. Use-after-free vulnerabilities occur when a program continues to use memory after it has been freed, potentially leading to memory corruption or arbitrary code execution. This specific vulnerability was reported by Tomer Fichman and has been fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The Mozilla advisory categorizes the impact as high and provides references to the bug report 2067190. There are no indications of active exploitation in the wild.
Potential Impact
The vulnerability poses a high impact risk as use-after-free bugs can lead to memory corruption, which may be exploited to execute arbitrary code or cause a denial of service. However, no active exploitation has been reported. Successful exploitation could compromise the security of affected Firefox installations.
Mitigation Recommendations
A fix for this vulnerability is available. Users and administrators should update to Firefox ESR 153.4, Firefox 157, or Firefox ESR 140.17 or later versions to remediate this issue. No additional mitigation actions are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:15:25.691Z
- 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/mfsa2026-99/","vendor":"Mozilla"}]
Threat ID: 6abbb3edf7a7c5410664096d
Added to database: 09/29/2026, 12:49:49 UTC
Last enriched: 09/29/2026, 13:33:26 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 2
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