Vulnerability in Mozilla Firefox
CVE-2025-1019
The z-order of the browser windows could be manipulated to hide the fullscreen notification. This could potentially be leveraged to perform a spoofing attack. This vulnerability was fixed in Firefox 135 and Thunderbird 135.
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.004 (27.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 27.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: -0.000
Affected products
- Mozilla Firefox — versions 135
- Mozilla Thunderbird — versions 135
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required)
- www.mozilla.org/security/advisories/mfsa2025-07/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-11/ (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-1019?
- CVE-2025-1019 is a medium-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 4.3/10. Published 2025-02-04.
- How severe is CVE-2025-1019?
- Medium severity. CVSS v3 base score is 4.3 out of 10.
- Is CVE-2025-1019 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.