CVE-2025-46507 is a Cross-Site Request Forgery (CSRF) vulnerability identified in the 'Unsafe Mimetypes' product developed by ldrumm, affecting versions up to 0.1.4. The vulnerability is categorized under CWE-352, which involves an attacker tricking an authenticated user into submitting a forged request to a web application without their consent. This specific vulnerability allows an attacker to perform stored Cross-Site Scripting (XSS) attacks by exploiting the CSRF flaw. Stored XSS occurs when malicious scripts injected by an attacker are permanently stored on the target server, such as in a database or log, and then executed in the browsers of users who access the affected content. The combination of CSRF and stored XSS significantly increases the attack surface, as an attacker can leverage CSRF to inject malicious scripts that persist and execute in victim browsers, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the user. The vulnerability affects the Unsafe Mimetypes product, which likely handles MIME type processing or filtering, although specific functionality details are not provided. No patches or fixes have been published yet, and there are no known exploits in the wild at this time. The vulnerability was publicly disclosed on April 24, 2025, and has been enriched by CISA, indicating recognition by a major cybersecurity authority. The absence of a CVSS score necessitates an independent severity assessment based on the potential impact and exploitability factors.

For European organizations, the impact of CVE-2025-46507 can be significant, especially for those relying on the Unsafe Mimetypes product or related web applications that process MIME types and handle user-generated content. The stored XSS enabled by the CSRF vulnerability can lead to unauthorized execution of scripts in the context of authenticated users, potentially compromising user accounts, leaking sensitive data, or enabling further attacks such as privilege escalation or lateral movement within corporate networks. This can affect confidentiality by exposing personal or corporate information, integrity by allowing unauthorized changes to data or application behavior, and availability if attackers disrupt services through malicious scripts. Sectors such as finance, healthcare, government, and critical infrastructure in Europe are particularly sensitive to such attacks due to regulatory requirements like GDPR and the potential for reputational damage. The lack of known exploits currently reduces immediate risk, but the presence of a stored XSS vector combined with CSRF makes this vulnerability attractive for attackers once exploit code becomes available. Organizations with web-facing applications using this product or similar MIME type handling components should consider this a medium to high risk depending on exposure and user base.

Given the absence of official patches, European organizations should implement immediate compensating controls. First, enforce strict anti-CSRF tokens on all state-changing requests to prevent unauthorized request forgery. Second, apply rigorous input validation and output encoding to mitigate stored XSS risks, ensuring that any user-supplied data is sanitized before storage and display. Third, conduct thorough code reviews and penetration testing focused on MIME type handling components to identify and remediate injection points. Fourth, implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. Fifth, monitor web application logs for unusual or suspicious requests indicative of exploitation attempts. Finally, maintain an inventory of affected software versions and plan for timely updates once patches become available. Organizations should also educate users about phishing and social engineering tactics that could facilitate CSRF attacks.