Vulnerability · Published Apr 30, 2025 · Assigned by mozilla
CVE-2025-3859Firefox Focus elide URL allows address bar spoofing
Medium 4.3
In plain English
A medium-severity security flaw in Focus from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).
Severity (CVSS 3.1)4.3Medium
Exploit odds (30 days)0.2%top 89.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
Weakness: CWE-451 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N