CVE-2026-100765: Vulnerability in Mozilla Firefox
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition within the JavaScript WebAssembly component of Mozilla Firefox. Use-after-free bugs occur when a program continues to use memory after it has been freed, potentially leading to crashes or arbitrary code execution. Mozilla fixed this issue in Firefox ESR 153.4 and Firefox 157. The vendor advisory categorizes the impact as high and references Bug 2061399 for technical details.
Potential Impact
The vulnerability has a high impact rating as per Mozilla's advisory, indicating serious memory safety concerns that could be leveraged to compromise the browser's security. However, there are no known active exploits in the wild at the time of this report.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4 and Firefox 157. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official update.
CVE-2026-100765: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.
CVSS v3.1
Score 8.8high
Affected software
Mozilla
Firefox
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition within the JavaScript WebAssembly component of Mozilla Firefox. Use-after-free bugs occur when a program continues to use memory after it has been freed, potentially leading to crashes or arbitrary code execution. Mozilla fixed this issue in Firefox ESR 153.4 and Firefox 157. The vendor advisory categorizes the impact as high and references Bug 2061399 for technical details.
Potential Impact
The vulnerability has a high impact rating as per Mozilla's advisory, indicating serious memory safety concerns that could be leveraged to compromise the browser's security. However, there are no known active exploits in the wild at the time of this report.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4 and Firefox 157. Users and administrators should update affected Firefox installations 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
- 2026-09-26T19:15:21.913Z
- 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"}]
Threat ID: 6abbb3ebf7a7c54106640943
Added to database: 09/29/2026, 12:49:47 UTC
Last enriched: 09/29/2026, 13:33:40 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 2
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