CVE-2022-41949 is a Server-Side Request Forgery (SSRF) vulnerability identified in the dhis2-core component of DHIS 2, an open-source platform widely used for data capture, management, validation, analytics, and visualization, especially in health information systems. The vulnerability affects multiple versions of DHIS 2 prior to specific hotfix releases (2.36.12.1, 2.37.8.1, 2.38.2.1, and 2.39.0.1). An authenticated user within the DHIS 2 system can craft specially designed requests that cause the server to initiate HTTP requests to arbitrary external or internal resources. This behavior can be exploited to scan internal networks or services that are not publicly accessible, potentially exposing sensitive internal infrastructure details or confirming the presence of specific files on the DHIS 2 server. The vulnerability leverages the server's trust and network access, allowing attackers to bypass network restrictions and potentially gather intelligence for further attacks. Notably, exploitation requires authentication, limiting the attack surface to users with valid credentials. As of the publication date, no known exploits have been reported in the wild, and no alternative mitigations beyond upgrading to the patched versions are available. The vulnerability is classified under CWE-918, which pertains to SSRF issues where an attacker can abuse server functionality to make unintended requests. This SSRF flaw could be used as a reconnaissance tool or as a stepping stone for more advanced attacks if combined with other vulnerabilities or misconfigurations.

For European organizations, especially those in the public health sector or NGOs using DHIS 2 for critical data management, this vulnerability poses a moderate risk. Exploitation could lead to unauthorized internal network scanning, exposing sensitive infrastructure details that are otherwise protected by network segmentation or firewalls. This could facilitate lateral movement or targeted attacks against internal services. While direct data exfiltration or system compromise is not guaranteed solely by this SSRF, the reconnaissance capability significantly increases the attacker's situational awareness and attack surface. Given DHIS 2's role in managing health data, any compromise or misuse could undermine data integrity and confidentiality indirectly by enabling further attacks. The requirement for authentication reduces the likelihood of widespread exploitation but raises concerns about insider threats or compromised user credentials. The absence of known exploits suggests limited immediate risk, but the availability of patches means organizations not updating are vulnerable to future attacks. The impact on availability is minimal, but the confidentiality and integrity of internal systems and data could be at risk if SSRF is chained with other vulnerabilities.

The primary and only effective mitigation is to upgrade DHIS 2 installations to the specified patched versions: 2.36.12.1, 2.37.8.1, 2.38.2.1, or 2.39.0.1, depending on the version in use. Organizations should prioritize patching in environments exposed to multiple users or where user credential compromise is more likely. Additionally, organizations should implement strict access controls and monitoring on DHIS 2 user accounts to detect unusual request patterns indicative of SSRF exploitation attempts. Network segmentation should be enforced to limit the server's ability to reach sensitive internal resources, minimizing the impact of SSRF if exploited. Web application firewalls (WAFs) can be tuned to detect and block suspicious outbound requests originating from the DHIS 2 server. Logging and alerting on outbound HTTP requests from the server can help identify exploitation attempts early. Finally, organizations should conduct regular audits of user privileges and enforce strong authentication mechanisms to reduce the risk of credential compromise.