What is CVE-2025-23108?

CVE-2025-23108 is a medium-severity vulnerability in Mozilla Firefox, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2025-01-11.

How severe is CVE-2025-23108?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Is CVE-2025-23108 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Mozilla Firefox

CVE-2025-23108

Opening Javascript links in a new tab via long-press in the Firefox iOS client could result in a malicious script spoofing the URL of the new tab. This vulnerability was fixed in Firefox for iOS 134.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2025-01-11 · last modified 2026-09-30.

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: 0.002 (13.6th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.6% 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
Mozilla Firefox For iOS — versions 134

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

RenwaX23/Address_

References

bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
www.mozilla.org/security/advisories/mfsa2025-06/ (Vendor Advisory)

Frequently asked questions

What is CVE-2025-23108?: CVE-2025-23108 is a medium-severity vulnerability in Mozilla Firefox, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2025-01-11.
How severe is CVE-2025-23108?: Medium severity. CVSS v3 base score is 4.3 out of 10.
Is CVE-2025-23108 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.