CVE-2025-7057 is a security vulnerability classified under CWE-79, which pertains to Improper Neutralization of Input During Web Page Generation, commonly known as Cross-site Scripting (XSS). This specific vulnerability affects the Quiz Extension of the Mediawiki software maintained by the Wikimedia Foundation. The affected versions include Mediawiki Quiz Extension releases from 1.39.x prior to 1.39.13, 1.42.x prior to 1.42.7, and 1.43.x prior to 1.43.2. The vulnerability is a Stored XSS flaw, meaning that malicious input submitted by an attacker is persistently stored on the server and later rendered in users’ browsers without proper sanitization or encoding. This allows attackers to inject arbitrary JavaScript code into web pages generated by the Quiz Extension. When other users access these pages, the malicious script executes in their browsers with the same privileges as the legitimate site, potentially leading to session hijacking, credential theft, defacement, or distribution of malware. The vulnerability arises from insufficient input validation or output encoding during the generation of web pages that display quiz content or user-submitted data. Although no known exploits are currently reported in the wild, the presence of stored XSS in a widely used extension for Mediawiki—a popular platform for collaborative knowledge bases and documentation—poses a significant risk. The lack of a CVSS score indicates this is a newly published issue, and remediation patches are expected but not yet linked in the provided data. The vulnerability affects multiple recent versions, indicating a persistent flaw across several releases.

For European organizations using Mediawiki with the Quiz Extension, this vulnerability can have serious consequences. Mediawiki is widely used in academic institutions, government agencies, and enterprises for documentation and knowledge sharing. Exploitation of this Stored XSS vulnerability could allow attackers to compromise user accounts, steal sensitive information, or manipulate content, undermining trust and confidentiality. In environments where Mediawiki hosts internal or sensitive data, the impact extends to potential data breaches and disruption of operations. Additionally, attackers could leverage the XSS flaw to conduct phishing attacks or spread malware within the organization’s network. Given the collaborative nature of Mediawiki, the vulnerability could facilitate lateral movement or privilege escalation if combined with other weaknesses. The absence of known exploits currently reduces immediate risk, but the public disclosure increases the likelihood of future attacks. European organizations must be vigilant, especially those in sectors with stringent data protection regulations like GDPR, as exploitation could lead to compliance violations and reputational damage.

Organizations should prioritize upgrading the Mediawiki Quiz Extension to the fixed versions: 1.39.13 or later, 1.42.7 or later, and 1.43.2 or later as applicable. Until patches are applied, administrators should consider disabling the Quiz Extension if feasible to eliminate the attack surface. Implementing Web Application Firewalls (WAFs) with rules to detect and block typical XSS payloads can provide interim protection. Additionally, organizations should audit user-generated content for suspicious scripts and enforce strict content security policies (CSP) to restrict script execution origins. Regular security training for administrators and users on recognizing phishing attempts and suspicious behavior can reduce the risk of exploitation. Monitoring logs for unusual activity related to Mediawiki pages containing quizzes is also recommended. Finally, organizations should subscribe to Wikimedia Foundation security advisories to receive timely updates on patches and vulnerability disclosures.