CVE-2025-1935
MEDIUMCVSS 4.3/10EPSS 0.32%
Last modified
CVE-2025-1935 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. A web page could trick a user into setting that site as the default handler for a custom URL protocol. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.. EPSS estimates a 0.32% chance of exploitation in the next 30 days.
Description
A web page could trick a user into setting that site as the default handler for a custom URL protocol. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 128.8.0 |
| Mozilla | Firefox | < 136.0 |
| Mozilla | Thunderbird | < 128.8.0 |
| Mozilla | Thunderbird | >= 129.0, < 136.0 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1866661Issue Tracking
- https://www.mozilla.org/security/advisories/mfsa2025-14/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-16/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-17/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-18/Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2025-1935?
A web page could trick a user into setting that site as the default handler for a custom URL protocol. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
How severe is CVE-2025-1935?
CVE-2025-1935 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 0.32% probability of exploitation in the next 30 days.
How do I fix CVE-2025-1935?
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.
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Are you affected by CVE-2025-1935?
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Scan your code nowSource: NVD / NIST