CVE-2025-64050 is a Remote Code Execution (RCE) vulnerability identified in the template management component of REDAXO CMS version 5.20.0. The vulnerability arises from insufficient input validation that allows authenticated administrators to inject arbitrary PHP code into active templates. When visitors access frontend pages rendered with these compromised templates, the injected PHP code executes on the server, enabling attackers to run arbitrary operating system commands. This can lead to full system compromise, including data theft, service disruption, or further lateral movement within the network. The vulnerability is classified under CWE-94 (Improper Control of Generation of Code). Exploitation requires valid administrator credentials, which implies that attackers must first gain or already possess elevated privileges within the CMS. No user interaction beyond accessing the affected frontend pages is necessary for the payload to execute. The CVSS v3.1 base score is 7.2, reflecting high severity due to network attack vector, low attack complexity, and high impact on confidentiality, integrity, and availability. As of the publication date, no patches or known exploits in the wild have been reported. The lack of patches necessitates immediate administrative controls and monitoring to mitigate risk. REDAXO CMS is used primarily by small to medium enterprises and organizations that prefer open-source CMS solutions, making the threat relevant to those sectors. The vulnerability's exploitation could enable attackers to establish persistent backdoors, exfiltrate sensitive data, or disrupt web services.

For European organizations, this vulnerability poses a significant risk, especially for those relying on REDAXO CMS for their web presence. Successful exploitation can lead to complete system compromise, resulting in data breaches, defacement of websites, or denial of service. Confidentiality is at risk due to potential data exfiltration; integrity is compromised as attackers can alter website content or backend data; availability may be affected if attackers disrupt services or deploy ransomware. Organizations in sectors such as government, finance, healthcare, and e-commerce, which often handle sensitive personal and financial data, face heightened risks. Additionally, compromised websites can be used as platforms for further attacks, including phishing or malware distribution, impacting the broader European digital ecosystem. The requirement for administrator credentials limits the attack surface but also highlights the criticality of securing privileged accounts. The absence of patches increases the window of exposure, making proactive defense essential.

1. Immediately audit and restrict administrator access to the REDAXO CMS, enforcing strong authentication mechanisms such as multi-factor authentication (MFA). 2. Monitor template management activities and implement logging to detect unauthorized or suspicious changes to templates. 3. Isolate the CMS environment to limit potential lateral movement if compromise occurs, using network segmentation and strict firewall rules. 4. Regularly back up website data and templates to enable rapid recovery in case of compromise. 5. Apply principle of least privilege to all CMS users, ensuring only necessary personnel have administrative rights. 6. Stay informed on REDAXO CMS vendor communications for official patches or updates addressing this vulnerability and apply them promptly once available. 7. Consider deploying Web Application Firewalls (WAFs) with custom rules to detect and block suspicious PHP code injections or unusual template modifications. 8. Conduct security awareness training for administrators to recognize phishing or social engineering attempts that could lead to credential compromise. 9. Perform regular vulnerability assessments and penetration testing focused on CMS components to identify and remediate weaknesses proactively.