CVE-2025-11718 is a security vulnerability identified in Mozilla Firefox for Android, affecting versions prior to 144. The issue arises when the browser's address bar is hidden due to user scrolling, a common behavior on mobile browsers to maximize screen real estate. During this state, a malicious webpage can exploit the visibilitychange event — a browser event triggered when the page visibility changes — to create and display a fake address bar overlay. This spoofed address bar can mimic the legitimate browser UI, misleading users into believing they are on a trusted website when they are not. This form of UI spoofing can facilitate phishing attacks by tricking users into entering sensitive information such as credentials or payment details. The vulnerability does not require any authentication or complex user interaction beyond visiting a malicious page. While no known exploits have been reported in the wild, the potential for abuse is significant given the widespread use of Firefox on Android devices. The lack of a CVSS score indicates the vulnerability is newly published, and no official severity rating has been assigned yet. The vulnerability specifically targets the integrity and confidentiality of user interactions by undermining the trustworthiness of the browser's address bar, a critical security indicator for users. The scope is limited to Firefox on Android, but given Firefox's market share in Europe, the impact could be notable. No patches or mitigation links are currently provided, emphasizing the need for prompt vendor response and user caution.

The primary impact of CVE-2025-11718 is the potential for phishing attacks through UI spoofing on Firefox for Android. European organizations relying on Firefox for mobile access to corporate resources or sensitive web services could see increased risk of credential theft or data compromise if users are deceived by fake address bars. This vulnerability threatens the confidentiality and integrity of user data by enabling attackers to impersonate legitimate sites convincingly. The availability of systems is not directly affected. Given the mobile-centric workflows in many European enterprises and the high penetration of Android devices, this vulnerability could facilitate targeted social engineering attacks against employees. Additionally, sectors such as finance, healthcare, and government, which often mandate secure browser usage, may face compliance and reputational risks if exploited. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as proof-of-concept attacks could emerge. The vulnerability's exploitation requires only that a user visit a malicious or compromised webpage, making it relatively easy to exploit and increasing the potential attack surface.

To mitigate CVE-2025-11718, European organizations should prioritize updating Mozilla Firefox on Android devices to version 144 or later once the patch is released. Until then, organizations can implement mobile device management (MDM) policies to restrict installation of untrusted applications and enforce browser usage policies that limit access to high-risk websites. User education campaigns should emphasize the risks of phishing and the importance of verifying website authenticity beyond the address bar, especially on mobile devices where UI spoofing is possible. Security teams can deploy web filtering solutions to block access to known malicious domains and monitor network traffic for suspicious activity indicative of phishing attempts. Additionally, encouraging the use of multi-factor authentication (MFA) can reduce the impact of credential theft resulting from such attacks. Organizations should also monitor Mozilla security advisories for updates and patches related to this vulnerability. Finally, developers and security teams should test internal web applications for susceptibility to UI spoofing and consider implementing Content Security Policy (CSP) headers to restrict script execution that could facilitate such attacks.