CVE-2026-92040: Vulnerability in Mozilla Firefox
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the JavaScript WebAssembly component of Mozilla Firefox. Use-after-free vulnerabilities occur when a program continues to use a pointer after the memory it points to has been freed, potentially leading to memory corruption or other unintended behavior. Mozilla fixed this issue in Firefox 156 as part of their security updates. The advisory is part of a broader set of individual advisories for memory safety vulnerabilities released by Mozilla.
Potential Impact
The impact is classified as moderate by Mozilla. Use-after-free vulnerabilities can lead to memory corruption, which might be leveraged to execute arbitrary code or cause a denial of service, but no specific exploitation in the wild is reported for this issue.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 156. Users and administrators should update to Firefox 156 or later to remediate this issue. No additional mitigation actions are required beyond applying the official update.
CVE-2026-92040: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the JavaScript WebAssembly component of Mozilla Firefox. Use-after-free vulnerabilities occur when a program continues to use a pointer after the memory it points to has been freed, potentially leading to memory corruption or other unintended behavior. Mozilla fixed this issue in Firefox 156 as part of their security updates. The advisory is part of a broader set of individual advisories for memory safety vulnerabilities released by Mozilla.
Potential Impact
The impact is classified as moderate by Mozilla. Use-after-free vulnerabilities can lead to memory corruption, which might be leveraged to execute arbitrary code or cause a denial of service, but no specific exploitation in the wild is reported for this issue.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 156. Users and administrators should update to Firefox 156 or later to remediate this issue. No additional mitigation actions are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-15T12:34:00.705Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-90/","vendor":"Mozilla"}]
Threat ID: 6aa93e6355bf5e2cf5d30ff8
Added to database: 09/15/2026, 12:47:31 UTC
Last enriched: 09/15/2026, 13:17:34 UTC
Last updated: 09/16/2026, 04:01:24 UTC
Views: 11
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