Vulnerability in Mozilla Firefox
CVE-2025-3033
After selecting a malicious Windows `.url` shortcut from the local filesystem, an unexpected file could be uploaded. *This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability was fixed in Firefox 137 and Thunderbird 137.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (6.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 6.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: -0.000
Affected products
- Mozilla Firefox — versions 137
- Mozilla Thunderbird — versions 137
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
- www.mozilla.org/security/advisories/mfsa2025-20/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-23/ (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-3033?
- CVE-2025-3033 is a high-severity vulnerability in Mozilla Firefox, classified under External Control of File Name or Path. CVSS score: 7.7/10. Published 2025-04-01.
- How severe is CVE-2025-3033?
- High severity. CVSS v3 base score is 7.7 out of 10.
- Is CVE-2025-3033 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.