CVE-2026-74946: Vulnerability in Mozilla Firefox
CVE-2026-74946 is a high-severity privilege escalation vulnerability in Mozilla Firefox affecting the Graphics: CanvasWebGL component due to incorrect boundary conditions. This flaw allows an attacker to escalate privileges within the browser environment. The vulnerability was fixed in Firefox 154 and corresponding ESR and Thunderbird versions. No known exploits are reported in the wild. Users should update to the fixed versions to mitigate the risk.
AI Analysis
Technical Summary
CVE-2026-74946 is a privilege escalation vulnerability caused by incorrect boundary conditions in the Graphics: CanvasWebGL component of Mozilla Firefox. This issue was identified and fixed in Firefox 154, Firefox ESR 115.39, ESR 140.14, ESR 153.1, and Thunderbird versions 154, 140.14, and 153.1. The vulnerability has a CVSS 3.1 base score of 8.8 (high severity) with network attack vector, low attack complexity, no privileges required, user interaction required, and impacts confidentiality, integrity, and availability. The vendor advisory confirms the fix and no known exploits in the wild.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser, potentially leading to unauthorized actions or access to sensitive information. The impact is rated high due to the potential for full compromise of the affected component's privileges.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154, Firefox ESR 115.39, ESR 140.14, ESR 153.1, and Thunderbird versions 154, 140.14, and 153.1. Users and administrators should update to these versions or later to remediate the vulnerability. No additional mitigation actions are required beyond applying the official updates.
CVE-2026-74946: Vulnerability in Mozilla Firefox
Description
CVE-2026-74946 is a high-severity privilege escalation vulnerability in Mozilla Firefox affecting the Graphics: CanvasWebGL component due to incorrect boundary conditions. This flaw allows an attacker to escalate privileges within the browser environment. The vulnerability was fixed in Firefox 154 and corresponding ESR and Thunderbird versions. No known exploits are reported in the wild. Users should update to the fixed versions to mitigate the risk.
CVSS v3.1
Score 8.8high
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-2026-74946 is a privilege escalation vulnerability caused by incorrect boundary conditions in the Graphics: CanvasWebGL component of Mozilla Firefox. This issue was identified and fixed in Firefox 154, Firefox ESR 115.39, ESR 140.14, ESR 153.1, and Thunderbird versions 154, 140.14, and 153.1. The vulnerability has a CVSS 3.1 base score of 8.8 (high severity) with network attack vector, low attack complexity, no privileges required, user interaction required, and impacts confidentiality, integrity, and availability. The vendor advisory confirms the fix and no known exploits in the wild.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser, potentially leading to unauthorized actions or access to sensitive information. The impact is rated high due to the potential for full compromise of the affected component's privileges.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154, Firefox ESR 115.39, ESR 140.14, ESR 153.1, and Thunderbird versions 154, 140.14, and 153.1. Users and administrators should update to these versions or later to remediate the vulnerability. No additional mitigation actions are required beyond applying the official updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:57:51.255Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-75/","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: 6a845504c6e8be03323673bf
Added to database: 08/18/2026, 12:50:12 UTC
Last enriched: 09/11/2026, 22:03:12 UTC
Last updated: 10/02/2026, 09:25:18 UTC
Views: 58
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