CVE-2025-3859: Vulnerability in Mozilla Focus
Websites directing users to long URLs that caused eliding to occur in the location view could leverage the truncating behavior to potentially trick users into thinking they were on a different webpage. This vulnerability was fixed in Focus 138.
AI Analysis
Technical Summary
This vulnerability involves the URL eliding behavior in Mozilla Focus for iOS, where websites using long URLs could cause the address bar to truncate the displayed URL in a way that misleads users about the actual destination. The issue is classified under CWE-451 (Incorrectly Controlled Modification of Object Prototype Attributes). The flaw was addressed and fixed in Focus version 138, eliminating the risk of address bar spoofing via URL truncation.
Potential Impact
The impact is limited to user deception through address bar spoofing, which could lead users to believe they are on a trusted site when they are not. There is no direct compromise of data confidentiality, integrity, or availability. The CVSS score of 4.3 (medium severity) reflects the limited scope of impact and the requirement for user interaction.
Mitigation Recommendations
Users and administrators should update Mozilla Focus for iOS to version 138 or later, where this vulnerability is fixed. No additional mitigation steps are required as the vendor has provided an official fix.
CVE-2025-3859: Vulnerability in Mozilla Focus
Description
Websites directing users to long URLs that caused eliding to occur in the location view could leverage the truncating behavior to potentially trick users into thinking they were on a different webpage. This vulnerability was fixed in Focus 138.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves the URL eliding behavior in Mozilla Focus for iOS, where websites using long URLs could cause the address bar to truncate the displayed URL in a way that misleads users about the actual destination. The issue is classified under CWE-451 (Incorrectly Controlled Modification of Object Prototype Attributes). The flaw was addressed and fixed in Focus version 138, eliminating the risk of address bar spoofing via URL truncation.
Potential Impact
The impact is limited to user deception through address bar spoofing, which could lead users to believe they are on a trusted site when they are not. There is no direct compromise of data confidentiality, integrity, or availability. The CVSS score of 4.3 (medium severity) reflects the limited scope of impact and the requirement for user interaction.
Mitigation Recommendations
Users and administrators should update Mozilla Focus for iOS to version 138 or later, where this vulnerability is fixed. No additional mitigation steps are required as the vendor has provided an official fix.
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-04-21T16:01:02.407Z
- Cisa Enriched
- true
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 682d9816c4522896dcbd6be3
Added to database: 5/21/2025, 9:08:38 AM
Last enriched: 4/14/2026, 11:45:23 AM
Last updated: 5/8/2026, 9:31:24 PM
Views: 71
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