CVE-2026-2074 identifies a security vulnerability in O2OA up to version 9.0.0, specifically in the HTTP POST request handler component located at /x_program_center/jaxrs/mpweixin/check. The flaw is an XML External Entity (XXE) injection vulnerability, which occurs when XML input containing external entity references is processed insecurely. This allows an attacker to craft malicious XML payloads that can cause the application to disclose internal files, perform server-side request forgery (SSRF), or potentially execute other unintended behaviors depending on the XML parser's configuration. The vulnerability can be triggered remotely without requiring user interaction or authentication, though the attacker needs low privileges (likely meaning some form of limited access or ability to send POST requests). The CVSS 4.0 base score is 5.3 (medium), reflecting moderate impact on confidentiality, integrity, and availability with relatively easy exploitation. The vendor was notified early but has not responded or issued a patch, and while a public exploit exists, no confirmed active exploitation in the wild has been reported. This vulnerability is significant because XXE attacks can lead to sensitive data leakage, denial of service, or internal network reconnaissance, especially in enterprise environments where O2OA is deployed for business process management or collaboration. The lack of vendor response and patch availability increases the urgency for organizations to implement mitigations.

For European organizations, the impact of CVE-2026-2074 can be substantial depending on their use of O2OA 9.0.0. The vulnerability can lead to unauthorized disclosure of sensitive internal files or data, undermining confidentiality. Integrity may be affected if attackers manipulate XML processing to alter application behavior or data. Availability could be impacted if the XXE payloads cause application crashes or resource exhaustion. Organizations handling sensitive personal data, intellectual property, or critical business processes via O2OA face increased risk of data breaches or operational disruption. The remote and unauthenticated nature of the exploit increases the attack surface, especially for internet-facing O2OA instances. The absence of vendor patches means organizations must rely on compensating controls to reduce risk. Given the GDPR environment in Europe, data exposure could also lead to regulatory penalties and reputational damage.

Since no official patch is available, European organizations should implement the following specific mitigations: 1) Disable external entity processing in the XML parser configuration used by O2OA if possible, to prevent XXE exploitation. 2) Employ Web Application Firewalls (WAFs) with rules to detect and block malicious XML payloads containing external entity references targeting the vulnerable endpoint. 3) Restrict network egress from the O2OA server to prevent SSRF and limit data exfiltration paths. 4) Monitor logs for unusual POST requests to /x_program_center/jaxrs/mpweixin/check and anomalous XML content. 5) Isolate O2OA servers in segmented network zones with strict access controls. 6) If feasible, upgrade or migrate away from O2OA 9.0.0 until a vendor patch is released. 7) Conduct internal code reviews or penetration tests focusing on XML input handling. 8) Educate administrators and developers about XXE risks and secure XML processing practices. These targeted actions go beyond generic advice and address the specific attack vector and environment.