CVE-2025-6431
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk15th percentile - higher than 15% of all known CVEs
Summary
When a link can be opened in an external application, Firefox for Android will, by default, prompt the user before doing so. An attacker could have bypassed this prompt, potentially exposing the user to security vulnerabilities or privacy leaks in external applications. This bug only affects Firefox for Android. Other versions of Firefox are unaffected. This vulnerability was fixed in Firefox 140.
Risk Assessment
A user could be tricked into opening a malicious link in an external application without warning, potentially leading to exploitation of vulnerabilities in that application or data leakage.
Recommendation
Update Firefox for Android to version 140 or later.
Other vulnerabilities in Firefox for Android
See all- CVE-2023-29534Critical
In Firefox and Focus for Android, techniques were discovered to obscure the fullscreen notification, which could lead to user confusion and spoofing attacks. This affects Firefox for Android and Focus for Android versions prior to 112.
- CVE-2026-100823Medium
Spoofing issue in the Downloads component in Firefox for Android. This vulnerability was fixed in Firefox 157.
- CVE-2026-92033High
Privilege escalation vulnerability in Firefox for Android. Fixed in Firefox 156.
- CVE-2026-84117High
Privilege escalation in Firefox for Android. Fixed in Firefox 155.
- CVE-2026-74975Medium
A spoofing issue exists in the Downloads component in Firefox for Android. This vulnerability was fixed in Firefox 154.
- CVE-2026-18809Medium
Information disclosure in Firefox for Android and Firefox Focus for Android. This vulnerability was fixed in Firefox 153.0.3.
- CVE-2026-16397Medium
Clickjacking vulnerability in the WebExtensions component in Firefox for Android. This issue was fixed in Firefox 153.
- CVE-2026-16373High
Vulnerability in the Privacy component in Firefox for Android. The flaw leads to information disclosure. The issue was fixed in Firefox 153.
- CVE-2025-8041Medium
In Firefox for Android, the address bar truncated the display of URLs from the end instead of prioritizing the origin. This vulnerability was fixed in Firefox 141.
- CVE-2025-6428Medium
Vulnerability in Firefox for Android where when a URL was provided in a link querystring parameter, the browser would follow that URL instead of the correct URL, potentially leading to phishing attacks. This bug only affects Firefox for Android and was fixed in Firefox 140.
Original NVD description (English source)
When a link can be opened in an external application, Firefox for Android will, by default, prompt the user before doing so. An attacker could have bypassed this prompt, potentially exposing the user to security vulnerabilities or privacy leaks in external applications. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.*. This vulnerability was fixed in Firefox 140.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

