CVE-2025-1935

Name: CVE-2025-1935
Creator: NVD / NIST
Published: 2025-03-04T14:15:38.39+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.3/10EPSS 0.32%

Last modified Jun 17, 2026

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

4.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

EPSS Probability

0.32%

23.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

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
https://lists.debian.org/debian-lts-announce/2025/03/msg00006.html

Timeline

Published: Mar 4, 2025
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2025-1935?

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.

Are you affected by CVE-2025-1935?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST