Attack Chain

1. Attacker gains privileged access to the CTMS or CPAS application, either through credential theft, phishing, or other means.
2. Attacker identifies the file upload functionality within the application.
3. Attacker crafts a malicious file, such as a PHP web shell, designed to execute arbitrary commands on the server.
4. Attacker bypasses any client-side file type validation mechanisms.
5. Attacker uploads the malicious file to the server through the vulnerable file upload endpoint.
6. The application saves the file to a publicly accessible directory without proper sanitization or validation.
7. Attacker accesses the uploaded web shell via a web browser.
8. Attacker uses the web shell to execute arbitrary commands on the server, leading to full system compromise.

Impact

Successful exploitation of CVE-2026-7490 allows attackers to execute arbitrary code on the affected server. This can lead to a range of malicious activities, including data theft, modification, or destruction, installation of malware, and complete system takeover. Since the vulnerability affects CTMS and CPAS, organizations in sectors utilizing these systems for content or process management are particularly at risk. The vulnerability’s high severity allows attackers to quickly gain a foothold and potentially compromise sensitive information or disrupt business operations.

Recommendation

• Apply available patches or updates from Sunnet to address CVE-2026-7490.
• Implement the Sigma rule Detect Malicious File Uploads to Web Servers to detect suspicious file uploads based on file extensions and content.
• Review and harden file upload functionalities within CTMS and CPAS to prevent arbitrary file uploads.
• Monitor web server logs for access to suspicious files in upload directories, using the Web Shell Access Sigma rule.
• Restrict access to file upload functionalities to only authorized users with appropriate privileges.