CVE-2024-23822 is a medium-severity vulnerability classified under CWE-22 (Improper Limitation of a Pathname to a Restricted Directory, commonly known as Path Traversal) affecting the Thruk monitoring web interface developed by sni. Thruk is a multibackend monitoring web application widely used for IT infrastructure monitoring and alerting. Prior to version 3.12, Thruk contains a flaw in its file upload functionality that allows an authenticated user with limited privileges (PR:L) to exploit a path traversal vulnerability. This vulnerability enables the attacker to upload arbitrary files to any location on the server's filesystem where the Thruk process has write permissions. The vulnerability does not require user interaction beyond authentication and can be exploited remotely (AV:N) with low attack complexity (AC:L). The impact primarily affects the integrity and availability of the system, as malicious files could be uploaded to overwrite critical files, deploy web shells, or disrupt monitoring operations. Confidentiality impact is rated none, as the vulnerability does not directly expose sensitive data. The issue was addressed in Thruk version 3.12 by properly restricting file upload paths to prevent directory traversal attacks. No known exploits are currently reported in the wild, but the vulnerability poses a significant risk if left unpatched due to the potential for arbitrary file write and subsequent system compromise.

For European organizations, this vulnerability poses a risk to the integrity and availability of critical IT monitoring infrastructure. Thruk is often deployed in enterprise environments, data centers, and managed service providers to monitor network and server health. Successful exploitation could allow attackers to upload malicious scripts or binaries, potentially leading to service disruption, unauthorized code execution, or pivoting within the network. This could impact operational continuity, incident response capabilities, and compliance with regulations such as GDPR if monitoring data or alerting systems are compromised. Given the role of monitoring tools in maintaining security posture, exploitation could delay detection of other attacks or system failures. Organizations relying on Thruk versions prior to 3.12 should prioritize patching to mitigate these risks. The lack of known active exploitation reduces immediate threat but does not eliminate risk, especially in targeted attacks against critical infrastructure or managed service providers in Europe.

1. Upgrade all Thruk installations to version 3.12 or later, which contains the fix for this path traversal vulnerability. 2. Restrict access to the Thruk web interface to trusted networks and enforce strong authentication controls to limit exposure to authenticated users only. 3. Implement file system permissions and access controls to minimize the directories writable by the Thruk process, reducing the impact scope if exploitation occurs. 4. Monitor logs for unusual file upload activity or unexpected file creations in the Thruk server directories. 5. Employ web application firewalls (WAFs) with rules to detect and block path traversal attempts in HTTP requests. 6. Conduct regular security audits and penetration tests focusing on file upload functionalities to detect similar vulnerabilities early. 7. Isolate monitoring infrastructure from critical production systems to limit lateral movement in case of compromise.