Vulnerability in Mozilla Firefox
CVE-2025-5020
Opening maliciously-crafted URLs in Firefox from other apps such as Safari could have allowed attackers to spoof website addresses if the URLs utilized non-HTTP schemes used internally by the Firefox iOS client. This vulnerability was fixe…
EPSS: 0.002 (9.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.
Affected products
- Mozilla Firefox
- Mozilla Firefox For Ios — versions 139
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (Permissions Required)
- security@mozilla.org (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-5020?
- CVE-2025-5020 is a medium-severity vulnerability in Mozilla Firefox, classified under CWE-939. CVSS score: 4.3/10. Published 2025-05-21.
- How severe is CVE-2025-5020?
- Medium severity. CVSS v3 base score is 4.3 out of 10.
- Is CVE-2025-5020 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.