Use-after-free in the JavaScript: WebAssembly component. (CVE-2026-100769)
A use-after-free vulnerability exists in the JavaScript: WebAssembly component of Firefox. This security flaw was addressed and fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The vulnerability has a high severity rating with a CVSS score of 8.8, indicating it could lead to significant impact if exploited.
AI Analysis
Technical Summary
CVE-2026-100769 is a use-after-free vulnerability in the JavaScript: WebAssembly component of Firefox. This type of vulnerability occurs when a program continues to use a pointer after it has been freed, potentially leading to memory corruption. The issue was reported by Tomer Fichman and has been fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The CVSS v3.1 base score is 8.8, reflecting high impact on confidentiality, integrity, and availability. The vulnerability is documented in Mozilla's security advisory MFSA 2026-100.
Potential Impact
The vulnerability allows an attacker to potentially execute arbitrary code or cause a denial of service by exploiting the use-after-free condition in the WebAssembly component. The CVSS vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability has been fixed by Mozilla in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. Users and administrators should update to these or later versions to mitigate the risk. No additional mitigation steps are required beyond applying the official update.
Use-after-free in the JavaScript: WebAssembly component. (CVE-2026-100769)
Description
A use-after-free vulnerability exists in the JavaScript: WebAssembly component of Firefox. This security flaw was addressed and fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The vulnerability has a high severity rating with a CVSS score of 8.8, indicating it could lead to significant impact if exploited.
CVSS v3.1
Score 8.8high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-100769 is a use-after-free vulnerability in the JavaScript: WebAssembly component of Firefox. This type of vulnerability occurs when a program continues to use a pointer after it has been freed, potentially leading to memory corruption. The issue was reported by Tomer Fichman and has been fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The CVSS v3.1 base score is 8.8, reflecting high impact on confidentiality, integrity, and availability. The vulnerability is documented in Mozilla's security advisory MFSA 2026-100.
Potential Impact
The vulnerability allows an attacker to potentially execute arbitrary code or cause a denial of service by exploiting the use-after-free condition in the WebAssembly component. The CVSS vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability has been fixed by Mozilla in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. Users and administrators should update to these or later versions to mitigate the risk. No additional mitigation steps are required beyond applying the official update.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-99h5-m2xx-wmr7
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-100769"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6abc27cb680226ef6846f8a3
Added to database: 09/29/2026, 21:04:11 UTC
Last enriched: 09/29/2026, 21:20:52 UTC
Last updated: 09/30/2026, 03:38:52 UTC
Views: 4
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