CVE-2021-44659 in GoCD
Summary
by MITRE • 12/22/2021
Adding a new pipeline in GoCD server version 21.3.0 has a functionality that could be abused to do an un-intended action in order to achieve a Server Side Request Forgery (SSRF)
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 08/04/2024
The vulnerability identified as CVE-2021-44659 resides within the GoCD server version 21.3.0 and represents a critical security flaw that enables unauthorized server-side request forgery attacks through the pipeline creation functionality. This vulnerability specifically affects the process of adding new pipelines to the GoCD continuous integration and delivery platform, where the system fails to properly validate or sanitize user input during pipeline configuration. The flaw allows an attacker to manipulate the pipeline creation process to initiate unintended network requests from the GoCD server to internal or external systems, potentially exposing sensitive infrastructure components and data.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the pipeline creation API endpoints. When users attempt to add new pipelines, the system processes configuration parameters without sufficient verification of their contents, particularly regarding URLs, endpoints, and network resource references. This lack of proper validation creates an attack surface where malicious actors can inject crafted parameters that trigger the GoCD server to make unauthorized HTTP requests to arbitrary destinations. The vulnerability operates at the server-side processing level, meaning that the malicious requests originate from the GoCD server itself rather than from external client systems, making detection and mitigation more challenging.
The operational impact of this vulnerability extends beyond simple unauthorized network access, as it can potentially enable attackers to perform reconnaissance activities against internal networks, access sensitive resources behind firewalls, and even facilitate further exploitation chains. An attacker could leverage this vulnerability to probe internal systems, access services that are not directly exposed to the internet, or potentially exfiltrate data from internal resources. The server-side nature of the attack means that the vulnerability could be exploited even when the GoCD server is properly firewalled, as the internal network connections initiated by the server itself bypass traditional network security controls. This makes the vulnerability particularly dangerous in environments where internal network segmentation is relied upon for security.
Security professionals should implement multiple layers of mitigation for this vulnerability, beginning with immediate patching of GoCD server instances to versions that address the specific input validation issues. Organizations should also consider implementing network-level restrictions that limit outbound connections from the GoCD server, particularly to internal resources that should not be accessible through pipeline configuration. The principle of least privilege should be enforced by restricting the GoCD server's network access capabilities and implementing strict firewall rules that prevent connections to sensitive internal systems. Additionally, monitoring and logging should be enhanced to detect unusual outbound network requests from the GoCD server, which could indicate exploitation attempts. This vulnerability aligns with CWE-918, which addresses server-side request forgery vulnerabilities, and maps to ATT&CK technique T1071.004 for application layer protocol tunneling and T1046 for network service scanning, emphasizing the reconnaissance and exploitation potential inherent in such server-side vulnerabilities.