CVE-2026-2761: Vulnerability in Mozilla Firefox
CVE-2026-2761 is a critical sandbox escape vulnerability in the Graphics: WebRender component of Mozilla Firefox. This vulnerability allows an attacker to potentially break out of the browser's sandbox environment. It was fixed in Firefox 148, Firefox ESR 115. 33, Firefox ESR 140. 8, Thunderbird 148, and Thunderbird 140. 8. The vulnerability has a CVSS score of 10. 0, indicating a critical severity with network attack vector, no required privileges or user interaction, and impacts confidentiality, integrity, and availability. There are no known exploits in the wild at the time of publication. Mozilla has issued official security advisories confirming the fix and urging users to update to the patched versions.
AI Analysis
Technical Summary
CVE-2026-2761 is a sandbox escape vulnerability in the Graphics: WebRender component of Mozilla Firefox and Thunderbird. The flaw allows an attacker to escape the sandbox protections, potentially leading to arbitrary code execution with elevated privileges. This vulnerability is part of a set of high-impact memory safety bugs fixed in Firefox 148 and ESR 115.33 releases. The CVSS 3.1 base score is 10.0, reflecting its critical nature and ease of exploitation without user interaction or privileges. The vendor advisory confirms the vulnerability was reported by Oskar L and fixed in the stated versions. No exploits are currently known in the wild.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the sandbox environment of Firefox's WebRender component, potentially leading to full compromise of the affected system. The CVSS score of 10.0 indicates critical impact on confidentiality, integrity, and availability. However, no active exploitation has been reported at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, patching the client software is required. There are no vendor advisories indicating that no action is required or that the issue is mitigated by other means.
CVE-2026-2761: Vulnerability in Mozilla Firefox
Description
CVE-2026-2761 is a critical sandbox escape vulnerability in the Graphics: WebRender component of Mozilla Firefox. This vulnerability allows an attacker to potentially break out of the browser's sandbox environment. It was fixed in Firefox 148, Firefox ESR 115. 33, Firefox ESR 140. 8, Thunderbird 148, and Thunderbird 140. 8. The vulnerability has a CVSS score of 10. 0, indicating a critical severity with network attack vector, no required privileges or user interaction, and impacts confidentiality, integrity, and availability. There are no known exploits in the wild at the time of publication. Mozilla has issued official security advisories confirming the fix and urging users to update to the patched versions.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-2761 is a sandbox escape vulnerability in the Graphics: WebRender component of Mozilla Firefox and Thunderbird. The flaw allows an attacker to escape the sandbox protections, potentially leading to arbitrary code execution with elevated privileges. This vulnerability is part of a set of high-impact memory safety bugs fixed in Firefox 148 and ESR 115.33 releases. The CVSS 3.1 base score is 10.0, reflecting its critical nature and ease of exploitation without user interaction or privileges. The vendor advisory confirms the vulnerability was reported by Oskar L and fixed in the stated versions. No exploits are currently known in the wild.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the sandbox environment of Firefox's WebRender component, potentially leading to full compromise of the affected system. The CVSS score of 10.0 indicates critical impact on confidentiality, integrity, and availability. However, no active exploitation has been reported at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, patching the client software is required. There are no vendor advisories indicating that no action is required or that the issue is mitigated by other means.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-02-19T15:05:25.145Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 699daf6bbe58cf853bdddd84
Added to database: 2/24/2026, 2:02:19 PM
Last enriched: 4/22/2026, 6:46:41 AM
Last updated: 5/26/2026, 7:56:06 AM
Views: 152
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.