CVE-2025-52353 is a critical arbitrary code execution vulnerability identified in Badaso CMS version 2.9.11. The vulnerability arises from the Media Manager component's file-upload endpoint, which allows authenticated users to upload files containing embedded PHP code. The system fails to properly validate the content type of uploaded files, enabling attackers to bypass restrictions and upload malicious files with embedded PHP payloads. An attacker can embed a backdoor within a file such as a PDF, rename it with a .php extension, and upload it via the Media Manager. When the uploaded file is accessed through its URL, the server executes the embedded PHP code, allowing the attacker to run arbitrary system commands. This results in full compromise of the underlying host, including potential access to sensitive data, system manipulation, and lateral movement within the network. Although no public exploits have been observed in the wild yet, the vulnerability's nature and ease of exploitation make it a significant threat. The vulnerability requires authentication, meaning the attacker must have valid user credentials or exploit another vulnerability to gain access to the upload functionality. However, once authenticated, the attacker can fully compromise the server by leveraging this flaw. No CVSS score has been assigned yet, but the technical details indicate a high-severity issue due to the potential for complete system takeover and the lack of effective content-type validation controls.

For European organizations using Badaso CMS 2.9.11, this vulnerability poses a severe risk. Successful exploitation can lead to full server compromise, resulting in unauthorized access to sensitive corporate data, disruption of services, and potential use of the compromised host as a pivot point for further attacks within the network. This can affect confidentiality, integrity, and availability of critical systems. Organizations in sectors such as government, finance, healthcare, and critical infrastructure are particularly at risk due to the sensitive nature of their data and regulatory requirements under GDPR and other European data protection laws. A breach could lead to significant financial penalties, reputational damage, and operational disruption. The requirement for authentication limits the attack surface but does not eliminate risk, especially if credential theft or phishing attacks are prevalent. Additionally, the ability to execute arbitrary system commands means attackers can deploy ransomware, steal data, or establish persistent backdoors, amplifying the threat's impact.

European organizations should immediately audit their Badaso CMS deployments to identify if version 2.9.11 or earlier vulnerable versions are in use. Since no official patch links are provided, organizations should consider the following specific mitigations: 1) Restrict access to the Media Manager upload functionality to only trusted and necessary users, implementing strict role-based access controls. 2) Implement additional server-side validation to verify file types beyond content-type headers, such as checking file signatures and disallowing executable extensions like .php in upload directories. 3) Configure the web server to prevent execution of PHP or other scripts in directories used for file uploads, for example, by disabling script execution in upload folders via .htaccess or equivalent configurations. 4) Monitor logs for suspicious upload activity and access to uploaded files with executable extensions. 5) Enforce multi-factor authentication (MFA) to reduce the risk of credential compromise. 6) If possible, upgrade to a patched version of Badaso CMS once available or apply vendor-provided workarounds. 7) Conduct regular security assessments and penetration testing focusing on file upload functionalities. These targeted actions go beyond generic advice and address the specific attack vector exploited by this vulnerability.