CVE-2026-12298: Vulnerability in Mozilla Firefox
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.
AI Analysis
Technical Summary
CVE-2026-12298 is a memory safety bug in Mozilla Firefox reported by Haruka Yamazaki and fixed in Firefox 152 and Firefox ESR 140.12. It is one of multiple high-impact memory safety vulnerabilities addressed in these versions, some of which showed evidence of memory corruption that could be exploited for arbitrary code execution. The issue affects Firefox 151 and ESR 140.11 and earlier versions prior to the fixes. Mozilla has published official security advisories MFSA 2026-57 and MFSA 2026-58 detailing these fixes.
Potential Impact
The vulnerability involves memory safety bugs that could lead to memory corruption. Such corruption may allow an attacker to execute arbitrary code within the context of the affected Firefox process. This poses a high security risk to users running vulnerable versions of Firefox and Firefox ESR prior to the patched releases.
Mitigation Recommendations
Official fixes for this vulnerability are available in Firefox 152 and Firefox ESR 140.12. 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 provided by Mozilla.
CVE-2026-12298: Vulnerability in Mozilla Firefox
Description
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.
CVSS v3.1
Score 5.4medium
Affected software
pkg:github/mozilla/firefox-esrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12298 is a memory safety bug in Mozilla Firefox reported by Haruka Yamazaki and fixed in Firefox 152 and Firefox ESR 140.12. It is one of multiple high-impact memory safety vulnerabilities addressed in these versions, some of which showed evidence of memory corruption that could be exploited for arbitrary code execution. The issue affects Firefox 151 and ESR 140.11 and earlier versions prior to the fixes. Mozilla has published official security advisories MFSA 2026-57 and MFSA 2026-58 detailing these fixes.
Potential Impact
The vulnerability involves memory safety bugs that could lead to memory corruption. Such corruption may allow an attacker to execute arbitrary code within the context of the affected Firefox process. This poses a high security risk to users running vulnerable versions of Firefox and Firefox ESR prior to the patched releases.
Mitigation Recommendations
Official fixes for this vulnerability are available in Firefox 152 and Firefox ESR 140.12. 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 provided by Mozilla.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:09.561Z
- 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"}]
Threat ID: 6a314c7b0b89be6888b4cbdf
Added to database: 6/16/2026, 1:15:39 PM
Last enriched: 6/16/2026, 1:46:34 PM
Last updated: 6/17/2026, 5:03:41 AM
Views: 6
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