Mozilla Firefox up to 143 on Android Focus UI ui layer

Summaryinfo

A vulnerability classified as problematic was found in Mozilla Firefox up to 143 on Android. This issue affects some unknown processing of the component Focus UI. Such manipulation leads to ui layer. This vulnerability is traded as CVE-2025-11720. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 143 on Android and classified as problematic. Affected by this issue is an unknown function of the component Focus UI. The manipulation with an unknown input leads to a ui layer vulnerability. Using CWE to declare the problem leads to CWE-1021. The web application does not restrict or incorrectly restricts frame objects or UI layers that belong to another application or domain, which can lead to user confusion about which interface the user is interacting with. Impacted is integrity. CVE summarizes:

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.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is handled as CVE-2025-11720 since 10/13/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 11/16/2025).

Upgrading to version 144 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-2275). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• IGEL OS
• Mozilla Firefox
• Mozilla Firefox ESR
• Mozilla Thunderbird

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox

Version

• 143

License

• open-source

Website

• Vendor: https://www.mozilla.org/
• Product: https://www.mozilla.org/en-US/firefox/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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