CVE-2025-11720

high

Description

The Firefox and Firefox Focus UI for the Android custom tab feature only showed the "site" that was loaded, not the full hostname. User supplied content hosted on a subdomain of a site could have been used to fool a user into thinking it was content from a different subdomain of that site. This vulnerability affects Firefox < 144.

References

https://www.mozilla.org/security/advisories/mfsa2025-81/

https://bugzilla.mozilla.org/show_bug.cgi?id=1984370

https://bugzilla.mozilla.org/show_bug.cgi?id=1979534

Details

Source: Mitre, NVD

Published: 2025-10-14

Updated: 2025-10-15

Risk Information

CVSS v2

Base Score: 9.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 8.1

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Severity: High

EPSS

EPSS: 0.00017