CVE-2026-100815: Vulnerability in Mozilla Firefox
Use-after-free in the CSS Parsing and Computation 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 in the CSS Parsing and Computation 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 as part of a broader security update addressing multiple high-impact vulnerabilities.
Potential Impact
The vulnerability is considered high impact by Mozilla, indicating it could allow an attacker to cause a crash or potentially execute arbitrary code. However, there are no known exploits in the wild currently. The fix mitigates the risk by correcting the use-after-free condition.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox ESR 153.4 and Firefox 157. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official update.
CVE-2026-100815: Vulnerability in Mozilla Firefox
Description
Use-after-free in the CSS Parsing and Computation 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 in the CSS Parsing and Computation 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 as part of a broader security update addressing multiple high-impact vulnerabilities.
Potential Impact
The vulnerability is considered high impact by Mozilla, indicating it could allow an attacker to cause a crash or potentially execute arbitrary code. However, there are no known exploits in the wild currently. The fix mitigates the risk by correcting the use-after-free condition.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox ESR 153.4 and Firefox 157. Users and administrators should update 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
- 2026-09-26T19:18:21.430Z
- 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: 6abbb3f5f7a7c541066409b7
Added to database: 09/29/2026, 12:49:57 UTC
Last enriched: 09/29/2026, 13:03:42 UTC
Last updated: 09/29/2026, 18:20:13 UTC
Views: 6
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