CVE-2025-53642 is a vulnerability identified in the haxtheweb project's HAXcms backends, specifically in the haxcms-nodejs and haxcms-php components. The issue stems from insufficient session expiration controls within the application's logout functionality. When a user logs out, the application fails to properly terminate the user's session or clear associated cookies, which are critical steps to ensure that session tokens cannot be reused maliciously. Moreover, the application paradoxically issues a refresh token upon logout, which is counterintuitive and exacerbates the risk by potentially allowing an attacker to obtain a valid token that can be used to regain access without re-authentication. This behavior violates secure session management best practices and is categorized under CWE-613: Insufficient Session Expiration. The vulnerability affects all versions prior to 11.0.6, where the issue has been addressed. The CVSS v3.1 base score is 4.8, indicating a medium severity level. The vector string (AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N) shows that the attack can be performed remotely over the network without privileges or user interaction, but requires high attack complexity. The impact on confidentiality and integrity is low, with no direct impact on availability. No known exploits are currently reported in the wild. This vulnerability could allow an attacker to hijack or maintain unauthorized access to user sessions after logout, potentially leading to unauthorized information disclosure or modification within the affected application environment.

For European organizations using HAXcms with the vulnerable haxcms-nodejs or haxcms-php backends, this vulnerability poses a risk of session hijacking or unauthorized session persistence. Attackers could exploit the failure to terminate sessions and the issuance of refresh tokens on logout to maintain or regain access to user accounts without proper authentication. This could lead to unauthorized access to sensitive content or administrative functions managed via HAXcms, potentially compromising data confidentiality and integrity. Although the CVSS score indicates medium severity and the attack complexity is high, organizations with sensitive or regulated data (such as those in finance, healthcare, or government sectors) could face compliance risks under GDPR if unauthorized access leads to personal data breaches. The lack of session termination also increases the risk in shared or public environments, where session tokens might be reused or stolen. Given that no user interaction is required and the attack vector is network-based, remote attackers could exploit this vulnerability without direct contact with the victim, increasing the threat surface. However, the absence of known exploits in the wild and the requirement for high attack complexity somewhat limit immediate widespread impact.

European organizations should prioritize upgrading all affected HAXcms backends (haxcms-nodejs and haxcms-php) to version 11.0.6 or later, where this vulnerability is fixed. Until the patch is applied, organizations should implement additional session management controls such as enforcing server-side session invalidation upon logout and ensuring that all session cookies are securely cleared. Web application firewalls (WAFs) can be configured to detect and block suspicious session token reuse patterns. Organizations should also audit their session handling policies to confirm that refresh tokens are not issued during logout processes and that token lifetimes are appropriately limited. Regular security testing, including session management assessments and penetration testing focused on authentication flows, is recommended to identify similar weaknesses. Additionally, monitoring for anomalous session activity and implementing multi-factor authentication (MFA) can reduce the risk of unauthorized access even if session tokens are compromised. Finally, educating developers on secure session management best practices will help prevent recurrence of such issues in future releases.