CVE-2025-57692 is a stored Cross-Site Scripting (XSS) vulnerability affecting PiranhaCMS version 12.0. The vulnerability exists in the Text content block of Standard and Standard Archive Pages, accessible via the /manager/pages interface. An attacker can inject arbitrary JavaScript code into these content blocks, which is then stored persistently on the server. When another user accesses the affected page through their browser, the malicious script executes in their context. This enables attackers to perform a range of malicious activities such as session hijacking, credential theft, defacement, or redirecting users to malicious sites. The vulnerability arises due to insufficient input sanitization or output encoding of user-supplied content within the CMS's page management interface. Since the injection point is within the administrative interface (/manager/pages), exploitation likely requires some level of authenticated access, although the exact authentication requirements are not specified. No official patch or CVSS score has been published yet, and there are no known exploits in the wild at the time of this report. Stored XSS vulnerabilities are particularly dangerous because the malicious payload is served to multiple users without requiring repeated attacker interaction, increasing the attack surface and potential impact.

For European organizations using PiranhaCMS 12.0, this vulnerability poses a significant risk to the confidentiality and integrity of user sessions and data. Attackers exploiting this flaw could hijack administrator or editor sessions, leading to unauthorized content changes, data leakage, or further compromise of internal systems. The stored nature of the XSS means that once injected, the malicious code can affect all users who access the infected pages, potentially including high-privilege users. This can lead to reputational damage, regulatory non-compliance (especially under GDPR if personal data is exposed), and operational disruption. Organizations relying on PiranhaCMS for public-facing or internal content management should be particularly cautious, as the vulnerability could be leveraged to spread malware or conduct phishing attacks targeting employees or customers. The lack of a patch and public exploit increases the urgency for proactive mitigation. Given the administrative interface is involved, insider threats or compromised credentials could facilitate exploitation, amplifying the risk.

European organizations should immediately audit their PiranhaCMS installations to identify usage of version 12.0 and the presence of Standard and Standard Archive Pages with Text content blocks. Until an official patch is released, it is critical to restrict access to the /manager/pages interface to trusted administrators only, ideally via network segmentation or VPN access. Implement strict input validation and output encoding on all user-supplied content within the CMS, possibly by deploying Web Application Firewalls (WAFs) with custom rules to detect and block suspicious script injections. Regularly review and sanitize existing content blocks to remove any malicious scripts. Enforce strong authentication mechanisms, including multi-factor authentication (MFA), for all CMS users to reduce the risk of credential compromise. Monitor logs for unusual activity around page management and user sessions. Additionally, consider deploying Content Security Policy (CSP) headers to limit the execution of unauthorized scripts in browsers. Finally, maintain close communication with PiranhaCMS vendors or security advisories for timely patch releases and updates.