CVE-2026-74944: Vulnerability in Mozilla Firefox
CVE-2026-74944 is a use-after-free vulnerability in the DOM: Core & HTML component of Mozilla Firefox. This critical security flaw was fixed in Firefox 154 and Firefox ESR versions 140.14 and 153.1. The vulnerability allows for potential high impact on confidentiality, integrity, and availability. It was reported by Amy Burnett of OpenAI and is part of a set of high-impact security issues addressed in these Firefox releases.
AI Analysis
Technical Summary
CVE-2026-74944 is a use-after-free vulnerability affecting the DOM: Core & HTML component in 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 and arbitrary code execution. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. The CVSS v3.1 base score is 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The fix is included in the official Mozilla security advisories MFSA 2026-74 and MFSA 2026-76.
Potential Impact
The vulnerability has a critical impact, allowing an attacker to potentially execute arbitrary code or cause denial of service by exploiting the use-after-free condition in the DOM Core & HTML component. The CVSS score of 9.8 reflects the high severity and potential for complete system compromise without requiring user interaction or privileges.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
CVE-2026-74944: Vulnerability in Mozilla Firefox
Description
CVE-2026-74944 is a use-after-free vulnerability in the DOM: Core & HTML component of Mozilla Firefox. This critical security flaw was fixed in Firefox 154 and Firefox ESR versions 140.14 and 153.1. The vulnerability allows for potential high impact on confidentiality, integrity, and availability. It was reported by Amy Burnett of OpenAI and is part of a set of high-impact security issues addressed in these Firefox releases.
CVSS v3.1
Score 9.8critical
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
pkg:github/mozilla/firefox-esrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-74944 is a use-after-free vulnerability affecting the DOM: Core & HTML component in 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 and arbitrary code execution. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. The CVSS v3.1 base score is 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The fix is included in the official Mozilla security advisories MFSA 2026-74 and MFSA 2026-76.
Potential Impact
The vulnerability has a critical impact, allowing an attacker to potentially execute arbitrary code or cause denial of service by exploiting the use-after-free condition in the DOM Core & HTML component. The CVSS score of 9.8 reflects the high severity and potential for complete system compromise without requiring user interaction or privileges.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:57:46.693Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-76/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-77/","vendor":"Mozilla"}]
Threat ID: 6a845504c6e8be03323673bb
Added to database: 08/18/2026, 12:50:12 UTC
Last enriched: 09/11/2026, 22:03:23 UTC
Last updated: 10/03/2026, 14:46:10 UTC
Views: 91
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