CVE-2025-53493 is a Stored Cross-site Scripting (XSS) vulnerability classified under CWE-79, affecting the MintyDocs extension of the Wikimedia Foundation's Mediawiki platform, specifically versions 1.43.x prior to 1.43.2. This vulnerability arises due to improper neutralization of input during web page generation, allowing malicious actors to inject and store arbitrary scripts within the web content served by the MintyDocs extension. When other users access the affected pages, the malicious scripts execute in their browsers, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the victim. The vulnerability has a CVSS 3.1 base score of 6.5, indicating a medium severity level. The vector details (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N) show that the attack can be executed remotely over the network without any privileges or user interaction, impacting confidentiality and integrity but not availability. No known exploits are currently reported in the wild, and no official patches have been linked yet, although the issue is reserved and published by the Wikimedia Foundation. The vulnerability specifically targets the MintyDocs extension, which is an add-on to Mediawiki, a widely used open-source wiki platform. Stored XSS vulnerabilities are particularly dangerous because the malicious payload persists on the server, affecting all users who view the compromised content. This can facilitate widespread exploitation if attackers manage to inject scripts into high-traffic or sensitive wiki pages.

For European organizations, the impact of this vulnerability depends largely on their use of Mediawiki with the MintyDocs extension. Mediawiki is commonly used for internal documentation, knowledge bases, and collaborative platforms in enterprises, government agencies, and educational institutions. A successful exploit could lead to unauthorized disclosure of sensitive information (confidentiality impact) and manipulation of content or user sessions (integrity impact). Although availability is not directly affected, the breach of trust and potential data leakage can have significant reputational and operational consequences. European organizations that rely on Mediawiki for critical documentation or that integrate it with other internal systems may face risks of lateral movement or further compromise if attackers leverage the XSS to execute additional attacks such as phishing or malware delivery. Additionally, compliance with EU data protection regulations (e.g., GDPR) could be jeopardized if personal data is exposed or manipulated through this vulnerability, leading to legal and financial repercussions.

To mitigate this vulnerability, European organizations should prioritize upgrading the MintyDocs extension to version 1.43.2 or later once it becomes available, as this will likely contain the official fix. Until then, organizations should implement strict input validation and output encoding on all user-supplied content within the MintyDocs extension to neutralize potentially malicious scripts. Employing Content Security Policy (CSP) headers can help restrict the execution of unauthorized scripts in browsers. Additionally, organizations should audit their Mediawiki installations to identify any instances of the MintyDocs extension and assess exposure. Monitoring logs for unusual activities or injection attempts can provide early detection of exploitation attempts. User privileges should be reviewed to limit who can create or edit content in the MintyDocs extension, reducing the attack surface. Finally, educating users about the risks of XSS and encouraging cautious behavior when interacting with wiki content can help mitigate social engineering vectors that might accompany exploitation.