CVE-2022-24789 in C1 CMS
Summary
by MITRE • 03/29/2022
C1 CMS is an open-source, .NET based Content Management System (CMS). Versions prior to 6.12 allow an authenticated user to exploit Server Side Request Forgery (SSRF) by causing the server to make arbitrary GET requests to other servers in the local network or on localhost. The attacker may also truncate arbitrary files to zero size (effectively delete them) leading to denial of service (DoS) or altering application logic. The authenticated user may unknowingly perform the actions by visiting a specially crafted site. Patched in C1 CMS v6.12, no known workarounds exist.
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Analysis
by VulDB Data Team • 03/31/2022
The vulnerability CVE-2022-24789 represents a critical server-side request forgery flaw in C1 CMS versions prior to 6.12, which operates on the .NET framework and serves as an open-source content management system. This vulnerability fundamentally compromises the security boundaries of the application by allowing authenticated users to manipulate the server's network communication capabilities. The flaw enables attackers to force the CMS server to initiate GET requests to internal network resources or localhost, effectively bypassing normal network segmentation controls that should protect internal systems from external access. The vulnerability stems from insufficient input validation and sanitization within the CMS's request handling mechanisms, specifically in how it processes user-supplied URLs or network addresses. This weakness directly maps to CWE-918, which categorizes server-side request forgery vulnerabilities that allow attackers to manipulate the target of a request to the server, and aligns with ATT&CK technique T1190 for exploiting vulnerabilities in web applications. The impact extends beyond simple information disclosure as the vulnerability also permits file truncation operations, where arbitrary files can be reduced to zero size, effectively deleting them and causing denial of service conditions. This dual nature of the vulnerability creates a particularly dangerous attack surface since it combines network reconnaissance capabilities with destructive file manipulation, potentially allowing attackers to disrupt application functionality or even corrupt critical application logic.
The operational impact of CVE-2022-24789 is significant for organizations relying on C1 CMS, as it transforms a single authenticated user account into a potential vector for internal network reconnaissance and disruption. An attacker with valid credentials can leverage this vulnerability to map internal network topology by making requests to various internal services, potentially discovering sensitive systems or applications that should remain isolated from public access. The ability to truncate files to zero size creates a substantial denial of service risk, particularly when targeting critical application components, configuration files, or database connection files that could render the CMS completely inoperable. This vulnerability can be exploited through social engineering tactics where users unknowingly visit malicious websites containing crafted URLs that trigger the SSRF behavior when the CMS processes them. The attack can occur without requiring special privileges or advanced technical skills, making it particularly dangerous in environments where users may inadvertently access compromised websites. The vulnerability's exploitation does not require knowledge of the internal network structure, as the CMS server itself will attempt to resolve and connect to the specified targets, potentially revealing internal services or systems that would otherwise be protected by network firewalls or security controls.
Organizations using C1 CMS versions prior to 6.12 must prioritize immediate remediation of this vulnerability through patch deployment, as no effective workarounds exist for this specific flaw. The patch released in C1 CMS version 6.12 addresses the core validation issues that allowed the SSRF attack vectors and prevents the file truncation capabilities that enable destructive operations. Security teams should conduct comprehensive vulnerability assessments to identify all systems running affected versions of the CMS and ensure proper patch management procedures are in place to prevent similar vulnerabilities in the future. The vulnerability highlights the importance of implementing proper input validation and sanitization controls, particularly for applications that process user-supplied network addresses or URLs, and demonstrates the critical need for network segmentation and access controls to limit the potential impact of such vulnerabilities. Organizations should also consider implementing web application firewalls or security monitoring solutions that can detect and prevent unauthorized network requests originating from their CMS servers, providing additional layers of protection against similar SSRF vulnerabilities. The vulnerability serves as a reminder of the importance of regularly updating and patching open-source applications, as the exploitation of such flaws can provide attackers with significant access to internal systems and potentially lead to more severe compromises within the broader network infrastructure.