CVE-2026-12289: Vulnerability in Mozilla Firefox
Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
AI Analysis
Technical Summary
CVE-2026-12289 is a privilege escalation vulnerability affecting the Graphics: WebRender component in Mozilla Firefox. The vulnerability was addressed and fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Mozilla's security advisories (MFSA2026-57 and MFSA2026-58) classify the impact as high and confirm that the issue has been resolved in these versions. The vulnerability is part of a broader set of security fixes released simultaneously, including multiple memory safety bugs and sandbox escapes. No CVSS score is provided, but the vendor impact rating is high. There are no reports of exploitation in the wild.
Potential Impact
The vulnerability allows privilege escalation within the WebRender graphics component of Firefox, which could enable an attacker to gain elevated privileges in the context of the browser process. This could potentially lead to further compromise of the system or user data if exploited. The vendor rates the impact as high. There are no known active exploits in the wild at the time of publication.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Users and administrators should update to these versions or later to remediate the issue. Since the vulnerability is fixed in these versions, no additional mitigation steps are required beyond applying the official update.
CVE-2026-12289: Vulnerability in Mozilla Firefox
Description
Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
CVSS v3.1
Score 8.8high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12289 is a privilege escalation vulnerability affecting the Graphics: WebRender component in Mozilla Firefox. The vulnerability was addressed and fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Mozilla's security advisories (MFSA2026-57 and MFSA2026-58) classify the impact as high and confirm that the issue has been resolved in these versions. The vulnerability is part of a broader set of security fixes released simultaneously, including multiple memory safety bugs and sandbox escapes. No CVSS score is provided, but the vendor impact rating is high. There are no reports of exploitation in the wild.
Potential Impact
The vulnerability allows privilege escalation within the WebRender graphics component of Firefox, which could enable an attacker to gain elevated privileges in the context of the browser process. This could potentially lead to further compromise of the system or user data if exploited. The vendor rates the impact as high. There are no known active exploits in the wild at the time of publication.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Users and administrators should update to these versions or later to remediate the issue. Since the vulnerability is fixed in these versions, no additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:05.525Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-57/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-58/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-59/","vendor":"Mozilla"}]
Threat ID: 6a314c7b0b89be6888b4cbad
Added to database: 6/16/2026, 1:15:39 PM
Last enriched: 6/16/2026, 2:00:08 PM
Last updated: 6/17/2026, 4:19:48 AM
Views: 4
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