CVE-2022-24789 is a Server-Side Request Forgery (SSRF) vulnerability identified in Orckestra's C1 CMS Foundation, an open-source .NET-based Content Management System. This vulnerability affects all versions prior to 6.12. SSRF vulnerabilities allow an attacker to abuse a server's functionality to send crafted requests from the server to other internal or external systems. In this case, an authenticated user can exploit the vulnerability to force the server to make arbitrary HTTP GET requests to internal network resources or localhost addresses. This can lead to unauthorized access to internal services that are otherwise inaccessible externally, potentially exposing sensitive internal data or services. Additionally, the vulnerability allows truncation of arbitrary files to zero size on the server, effectively deleting them. This file truncation can cause denial of service (DoS) conditions by disrupting application logic or deleting critical files. Notably, exploitation requires authentication, but the attacker can trick an authenticated user into performing these actions unknowingly by visiting a specially crafted malicious website, indicating a potential for social engineering or cross-site attack vectors. The vulnerability was patched in version 6.12 of C1 CMS, and no known workarounds exist, emphasizing the importance of upgrading. There are no known exploits in the wild reported to date. The vulnerability is classified under CWE-918 (Server-Side Request Forgery), which highlights the risk of unauthorized internal network access and manipulation of server-side resources through crafted requests. The lack of a CVSS score necessitates an independent severity assessment based on impact and exploitability factors.

For European organizations using Orckestra C1 CMS Foundation versions prior to 6.12, this vulnerability poses several risks. The SSRF aspect can allow attackers to pivot within internal networks, potentially accessing sensitive internal services such as databases, internal APIs, or administrative interfaces that are not exposed externally. This could lead to data breaches or unauthorized internal reconnaissance. The ability to truncate files arbitrarily can disrupt website functionality, cause data loss, or lead to denial of service, impacting business continuity and user trust. Since exploitation requires authentication, the threat is primarily from insiders or attackers who have compromised user credentials. However, the possibility of tricking authenticated users into visiting malicious sites increases the attack surface through social engineering. The impact on confidentiality, integrity, and availability is significant: confidentiality is threatened by SSRF-based internal access; integrity is compromised by file truncation altering application behavior; availability is affected by potential denial of service. Given that C1 CMS is used in content management, organizations relying on it for public-facing websites or internal portals could experience reputational damage and operational disruption. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits over time.

1. Immediate upgrade to Orckestra C1 CMS Foundation version 6.12 or later to apply the official patch addressing this vulnerability. 2. Implement strict network segmentation and firewall rules to limit the server's ability to make outbound HTTP requests to internal services, reducing the SSRF attack surface. 3. Enforce strong authentication and session management policies to prevent credential compromise and reduce the risk of unauthorized authenticated access. 4. Educate users about phishing and social engineering risks to minimize the chance of them visiting maliciously crafted sites that could trigger exploitation. 5. Monitor server logs for unusual outbound requests or file truncation activities that could indicate exploitation attempts. 6. Employ Web Application Firewalls (WAFs) with SSRF detection capabilities to block suspicious request patterns. 7. Conduct regular security audits and penetration testing focused on SSRF and file manipulation vulnerabilities within the CMS environment. 8. Restrict file system permissions for the CMS process to prevent unauthorized file truncation or deletion beyond what is necessary for normal operation.