CVE-2024-10462 is a vulnerability identified in Mozilla Firefox and Thunderbird that allows an attacker to spoof the origin displayed in permission prompts by exploiting the truncation of long URLs. When a URL exceeds a certain length, the browser truncates it in the permission prompt UI, which can be manipulated to display a misleading origin. This spoofing can deceive users into granting permissions (such as location access, notifications, or camera/microphone use) to malicious websites masquerading as legitimate ones. The vulnerability affects Firefox versions earlier than 132 and Thunderbird versions earlier than 128.4 and 132. The flaw stems from improper handling of URL length in the UI rendering of permission prompts, categorized under CWE-290 (Authentication Bypass by Spoofing). The CVSS 3.1 base score is 7.5, indicating high severity, with an attack vector of network (remote), low attack complexity, no privileges required, no user interaction needed, and impact limited to integrity (misleading users to grant permissions). Although no exploits have been observed in the wild, the potential for phishing and social engineering attacks leveraging this vulnerability is significant. The vulnerability does not directly compromise confidentiality or availability but undermines user trust and security decisions, potentially leading to unauthorized access to sensitive device capabilities. The issue highlights the importance of accurate UI representation in security prompts to prevent spoofing attacks. Mozilla is expected to release patches addressing this truncation and spoofing issue in upcoming Firefox and Thunderbird versions.

For European organizations, this vulnerability poses a significant risk as it can lead to unauthorized permission grants to malicious websites, potentially enabling further attacks such as malware installation, data leakage, or surveillance. Organizations relying heavily on Firefox and Thunderbird for web browsing and email communications are particularly vulnerable. The integrity of user decisions is compromised, which can facilitate phishing campaigns and social engineering attacks targeting employees. This can result in unauthorized access to sensitive resources, breach of privacy regulations (such as GDPR), and potential reputational damage. The lack of required user interaction or privileges lowers the barrier for exploitation, increasing the threat landscape. Critical sectors such as finance, government, healthcare, and telecommunications in Europe could face targeted attacks exploiting this vulnerability to gain footholds in networks or exfiltrate sensitive information. The vulnerability also affects endpoint security posture, as compromised permissions can lead to persistent device-level threats. Overall, the impact is high due to the potential for cascading security failures initiated by spoofed permission prompts.

European organizations should prioritize updating Mozilla Firefox to version 132 or later and Thunderbird to versions 128.4 or 132 once patches are released. Until patches are available, organizations should implement strict browser usage policies, including restricting the use of outdated browser versions through endpoint management solutions. User awareness training should emphasize vigilance when responding to permission prompts, especially scrutinizing the origin displayed. Deploying web filtering and endpoint detection tools can help identify and block malicious URLs exploiting this vulnerability. Organizations should consider disabling non-essential permissions in browser settings to minimize attack surface. Monitoring network traffic for suspicious activity related to permission requests can provide early detection of exploitation attempts. Security teams should review and tighten policies around browser extensions and plugins, which could be leveraged in conjunction with this vulnerability. Finally, coordinating with Mozilla’s security advisories and subscribing to vulnerability feeds will ensure timely response to updates and patches.