CVE-2026-100789: Vulnerability in Mozilla Firefox
Use-after-free in the Graphics: Canvas2D 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 Canvas2D graphics 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 security issues. Mozilla fixed this issue in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory categorizes the impact as high and lists this vulnerability among multiple high-impact security fixes in the Firefox ESR 153.4 release.
Potential Impact
The vulnerability has a high impact rating according to Mozilla, indicating it could potentially allow attackers to cause memory corruption or other serious security consequences if exploited. However, there are no known exploits in the wild currently. The flaw affects the Canvas2D graphics component, which is integral to rendering graphics in Firefox.
Mitigation Recommendations
A fix is available and has been released by Mozilla. Users and administrators should update to Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, Firefox ESR 140.17, or later versions to remediate this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-100789: Vulnerability in Mozilla Firefox
Description
Use-after-free in the Graphics: Canvas2D 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
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the Canvas2D graphics 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 security issues. Mozilla fixed this issue in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory categorizes the impact as high and lists this vulnerability among multiple high-impact security fixes in the Firefox ESR 153.4 release.
Potential Impact
The vulnerability has a high impact rating according to Mozilla, indicating it could potentially allow attackers to cause memory corruption or other serious security consequences if exploited. However, there are no known exploits in the wild currently. The flaw affects the Canvas2D graphics component, which is integral to rendering graphics in Firefox.
Mitigation Recommendations
A fix is available and has been released by Mozilla. Users and administrators should update to Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, Firefox ESR 140.17, or later versions to remediate this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:17:15.797Z
- 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: 6abbb3f1f7a7c5410664098d
Added to database: 09/29/2026, 12:49:53 UTC
Last enriched: 09/29/2026, 13:18:41 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 3
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