CVE-2026-12311
MEDIUMCVSS 4.7/10EPSS 0.18%
Last modified
CVE-2026-12311 is a medium-severity vulnerability rated 4.7/10 on the CVSS scale. Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.. EPSS estimates a 0.18% chance of exploitation in the next 30 days.
Description
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 152.0 |
| Mozilla | Firefox | >= 140.0, < 140.12.0 |
| Mozilla | Thunderbird | < 152.0.0 |
| Mozilla | Thunderbird | >= 140.0, < 140.12.0 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2040177Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-57/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-58/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-60/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-61/Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-12311?
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
How severe is CVE-2026-12311?
CVE-2026-12311 has a CVSS score of 4.7/10 (MEDIUM severity). The EPSS model estimates a 0.18% probability of exploitation in the next 30 days.
How do I fix CVE-2026-12311?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-12306Memory safety bug fixed in Firefox 152. This vulnerability w…5.3
- CVE-2026-12307Memory safety bug fixed in Firefox 152. This vulnerability w…5.3
- CVE-2026-12308Memory safety bug fixed in Firefox 152. This vulnerability w…5.3
- CVE-2026-12309Memory safety bug fixed in Firefox 152. This vulnerability w…6.5
- CVE-2026-1231The Beaver Builder Page Builder – Drag and Drop Website Buil…6.4
- CVE-2026-12310Memory safety bug fixed in Firefox 152. This vulnerability w…7.5
- CVE-2026-12312Memory safety bug fixed in Firefox 152. This vulnerability w…7.5
- CVE-2026-12313Information disclosure, sandbox escape in the Security: Proc…4.7
- CVE-2026-12314Memory safety bug fixed in Firefox 152. This vulnerability w…7.5
- CVE-2026-12315Mitigation bypass in the DOM: Security component. This vulne…9.1
- CVE-2026-12316Mitigation bypass in the DOM: Security component. This vulne…9.1
- CVE-2026-12317Memory safety bug fixed in Firefox 152. This vulnerability w…7.5
Are you affected by CVE-2026-12311?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST