What is CVE-2025-55033?

CVE-2025-55033 is a medium-severity vulnerability in Mozilla Firefox Focus, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2025-08-19.

How severe is CVE-2025-55033?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Mozilla Firefox Focus

CVE-2025-55033

Dragging JavaScript links to the URL bar in Focus for iOS could be utilized to run malicious scripts, potentially resulting in XSS attacks. This vulnerability was fixed in Focus for iOS 142.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2025-08-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (5.5th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.5% 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 Focus
Mozilla Focus For iOS — versions 142

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
www.mozilla.org/security/advisories/mfsa2025-69/ (Vendor Advisory)

Frequently asked questions

What is CVE-2025-55033?: CVE-2025-55033 is a medium-severity vulnerability in Mozilla Firefox Focus, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2025-08-19.
How severe is CVE-2025-55033?: Medium severity. CVSS v3 base score is 6.1 out of 10.