CVE-2026-2781
CRITICALCVSS 9.8/10EPSS 0.36%
Last modified
CVE-2026-2781 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, Thunderbird 140.8, and Firefox ESR 115.35.. EPSS estimates a 0.36% chance of exploitation in the next 30 days.
Description
Integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, Thunderbird 140.8, and Firefox ESR 115.35.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 140.8.0 |
| Mozilla | Firefox | < 148.0 |
| Mozilla | Thunderbird | < 140.8.0 |
| Mozilla | Thunderbird | < 148.0 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2009552Issue Tracking, Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-13/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-15/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-16/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-17/Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2026-2781?
Integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, Thunderbird 140.8, and Firefox ESR 115.35.
How severe is CVE-2026-2781?
CVE-2026-2781 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.36% probability of exploitation in the next 30 days.
How do I fix CVE-2026-2781?
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-2026-27803Vaultwarden is an unofficial Bitwarden compatible server wri…8.3
- CVE-2026-27804Parse Server is an open source backend that can be deployed …9.1
- CVE-2026-27806Fleet is open source device management software. Prior to 4.…7.8
- CVE-2026-27807MarkUs is a web application for the submission and grading o…4.9
- CVE-2026-27808Mailpit is an email testing tool and API for developers. Pri…8.6
- CVE-2026-27809psd-tools is a Python package for working with Adobe Photosh…9.1
- CVE-2026-27810calibre is a cross-platform e-book manager for viewing, conv…6.4
- CVE-2026-27811Roxy-WI is a web interface for managing Haproxy, Nginx, Apac…8.8
- CVE-2026-27812Sub2API is an AI API gateway platform designed to distribute…9.1
- CVE-2026-27813EVerest is an EV charging software stack. Versions prior to …5.3
- CVE-2026-27814EVerest is an EV charging software stack. Versions prior to …4.2
- CVE-2026-27815EVerest is an EV charging software stack. Prior to versions …9.1
Are you affected by CVE-2026-2781?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST