CVE-2025-1935: Vulnerability in Mozilla Firefox
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.
AI Analysis
Technical Summary
CVE-2025-1935 is a clickjacking vulnerability in Mozilla Firefox that could allow a malicious web page to deceive a user into setting that site as the default handler for a custom URL protocol via the registerProtocolHandler info-bar. This vulnerability was fixed in Firefox 136 and Firefox ESR 128.8. The vulnerability is categorized under CWE-79 (Improper Neutralization of Input During Web Page Generation). The vendor advisories confirm that the issue is resolved in the specified Firefox versions. The CVSS 3.1 vector indicates the attack requires no privileges but user interaction and results in limited confidentiality impact without integrity or availability impact.
Potential Impact
The impact of CVE-2025-1935 is limited to a low-severity clickjacking scenario where a user could be tricked into associating a malicious site as the handler for a custom URL protocol. This could potentially lead to unintended behavior when such URLs are invoked, but does not directly allow code execution or system compromise. There are no known exploits in the wild for this vulnerability. The fix in Firefox 136 and Firefox ESR 128.8 mitigates this risk.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 136 and Firefox ESR 128.8. Users and administrators should update affected Firefox and Thunderbird versions to these or later releases to remediate the issue. Since the vulnerability requires user interaction and is fixed in the latest versions, no additional mitigation steps are necessary beyond applying the official update.
CVE-2025-1935: Vulnerability in Mozilla Firefox
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.
CVSS v3.1
Score 4.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-1935 is a clickjacking vulnerability in Mozilla Firefox that could allow a malicious web page to deceive a user into setting that site as the default handler for a custom URL protocol via the registerProtocolHandler info-bar. This vulnerability was fixed in Firefox 136 and Firefox ESR 128.8. The vulnerability is categorized under CWE-79 (Improper Neutralization of Input During Web Page Generation). The vendor advisories confirm that the issue is resolved in the specified Firefox versions. The CVSS 3.1 vector indicates the attack requires no privileges but user interaction and results in limited confidentiality impact without integrity or availability impact.
Potential Impact
The impact of CVE-2025-1935 is limited to a low-severity clickjacking scenario where a user could be tricked into associating a malicious site as the handler for a custom URL protocol. This could potentially lead to unintended behavior when such URLs are invoked, but does not directly allow code execution or system compromise. There are no known exploits in the wild for this vulnerability. The fix in Firefox 136 and Firefox ESR 128.8 mitigates this risk.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 136 and Firefox ESR 128.8. Users and administrators should update affected Firefox and Thunderbird versions to these or later releases to remediate the issue. Since the vulnerability requires user interaction and is fixed in the latest versions, no additional mitigation steps are necessary beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-03-04T12:29:38.170Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2025-14/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-16/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-17/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-18/","vendor":"Mozilla"}]
Threat ID: 69091a4ac28fd46ded81d067
Added to database: 11/03/2025, 21:10:34 UTC
Last enriched: 06/04/2026, 19:53:35 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 89
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