CVE-2025-10535 is a vulnerability identified in the Privacy component of Mozilla Firefox for Android, affecting all versions prior to 143. It is classified under CWE-200, indicating an information disclosure weakness. The vulnerability enables an attacker to bypass privacy mitigations, potentially exposing sensitive user information that should otherwise be protected by Firefox's privacy controls. The CVSS v3.1 base score is 7.5, reflecting high severity, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction needed (UI:N). The scope is unchanged (S:U), and the impact is primarily on integrity (I:H) without affecting confidentiality (C:N) or availability (A:N). This suggests that while confidential data may not be directly leaked, the integrity of privacy protections is compromised, possibly allowing unauthorized access or manipulation of private data. No known exploits have been reported in the wild, and no official patches have been linked yet, indicating that the vulnerability is newly disclosed. The issue specifically targets Firefox on Android, which is widely used across Europe, making mobile users particularly vulnerable. The lack of required authentication and user interaction increases the risk of exploitation, as attackers can remotely trigger the vulnerability without user awareness. The vulnerability's presence in the Privacy component highlights a critical failure in safeguarding user data, which could have broader implications for user trust and regulatory compliance.

For European organizations, this vulnerability poses a significant risk to the integrity of privacy protections on mobile devices running Firefox for Android. Organizations that rely on Firefox for secure browsing or handle sensitive personal or corporate data on mobile platforms could face unauthorized exposure or manipulation of private information. This could lead to data integrity issues, undermining trust in privacy controls and potentially violating data protection regulations such as GDPR. The lack of confidentiality impact reduces the risk of direct data leaks, but the bypass of privacy mitigations could facilitate further attacks or data misuse. The vulnerability's remote exploitability without user interaction increases the attack surface, especially in sectors with high mobile usage like finance, healthcare, and government. Additionally, the absence of patches at the time of disclosure means organizations must rely on interim mitigations, increasing operational risk. The impact is amplified in environments where mobile device security is critical, and where Firefox is a primary browser choice. Overall, this vulnerability could disrupt secure mobile operations and expose organizations to compliance and reputational risks.

Organizations should prioritize updating Firefox for Android to version 143 or later as soon as the patch becomes available. Until then, they should enforce strict mobile device management (MDM) policies to control browser usage and restrict access to sensitive resources from vulnerable devices. Implement network-level protections such as web filtering and intrusion detection systems to monitor and block suspicious traffic targeting Firefox browsers. Educate users about the risks of using outdated browser versions and encourage prompt updates. Consider deploying alternative secure browsers temporarily if critical operations depend on uncompromised privacy protections. Regularly audit and monitor mobile device configurations to ensure compliance with security policies. Collaborate with Mozilla and security communities to stay informed about patch releases and exploit developments. For highly sensitive environments, consider isolating Firefox usage or employing containerization to limit potential data exposure. Finally, review and enhance privacy settings within Firefox to minimize the attack surface until the vulnerability is remediated.