CVE-2026-6763: Vulnerability in Mozilla Firefox
CVE-2026-6763 is a mitigation bypass vulnerability in the File Handling component of Mozilla Firefox. This vulnerability was addressed and fixed in Firefox 150 and Firefox ESR 140. 10. The issue is classified with moderate impact according to the Mozilla advisory. Multiple related vulnerabilities affecting Firefox and Firefox ESR were fixed simultaneously in these versions, including several high-impact memory safety bugs. No known exploits in the wild have been reported for this specific vulnerability.
AI Analysis
Technical Summary
CVE-2026-6763 is a mitigation bypass vulnerability located in the File Handling component of Mozilla Firefox. The vulnerability was publicly disclosed and fixed in Firefox 150 and Firefox ESR 140.10 releases. The Mozilla advisories indicate the impact level as moderate for this issue. The fix is part of a broader security update that addresses numerous vulnerabilities, including high-impact memory safety bugs and other mitigation bypasses across various Firefox components. The vendor has released official patches for this vulnerability.
Potential Impact
The vulnerability allows bypassing security mitigations in the File Handling component, which could potentially weaken Firefox's security posture. The impact is assessed as moderate by Mozilla. There are no reports of active exploitation in the wild. The fix is included in Firefox 150 and Firefox ESR 140.10, which also address several other critical and high-impact vulnerabilities.
Mitigation Recommendations
Mozilla has released official fixes for CVE-2026-6763 in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these or later versions to remediate this vulnerability. Since the vulnerability is fixed in these releases, no additional mitigation steps are required beyond applying the official update.
CVE-2026-6763: Vulnerability in Mozilla Firefox
Description
CVE-2026-6763 is a mitigation bypass vulnerability in the File Handling component of Mozilla Firefox. This vulnerability was addressed and fixed in Firefox 150 and Firefox ESR 140. 10. The issue is classified with moderate impact according to the Mozilla advisory. Multiple related vulnerabilities affecting Firefox and Firefox ESR were fixed simultaneously in these versions, including several high-impact memory safety bugs. No known exploits in the wild have been reported for this specific vulnerability.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-6763 is a mitigation bypass vulnerability located in the File Handling component of Mozilla Firefox. The vulnerability was publicly disclosed and fixed in Firefox 150 and Firefox ESR 140.10 releases. The Mozilla advisories indicate the impact level as moderate for this issue. The fix is part of a broader security update that addresses numerous vulnerabilities, including high-impact memory safety bugs and other mitigation bypasses across various Firefox components. The vendor has released official patches for this vulnerability.
Potential Impact
The vulnerability allows bypassing security mitigations in the File Handling component, which could potentially weaken Firefox's security posture. The impact is assessed as moderate by Mozilla. There are no reports of active exploitation in the wild. The fix is included in Firefox 150 and Firefox ESR 140.10, which also address several other critical and high-impact vulnerabilities.
Mitigation Recommendations
Mozilla has released official fixes for CVE-2026-6763 in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these or later versions to remediate this vulnerability. Since the vulnerability is fixed in these releases, no additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-04-21T12:40:57.216Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-30/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-32/","vendor":"Mozilla"}]
Threat ID: 69e7789c19fe3cd2cdd163ee
Added to database: 4/21/2026, 1:16:12 PM
Last enriched: 4/21/2026, 1:33:47 PM
Last updated: 4/21/2026, 5:05:04 PM
Views: 3
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