CVE-2025-6810 is a critical remote code execution vulnerability found in Mescius ActiveReports.NET version 18.1.1. The flaw resides in the ReadValue method, which improperly handles deserialization of untrusted data. Specifically, the method lacks sufficient validation of user-supplied input before deserializing it, leading to the possibility that an attacker can craft malicious serialized data to execute arbitrary code within the context of the running process. This vulnerability is classified under CWE-502 (Deserialization of Untrusted Data), a common and dangerous security weakness that can allow attackers to bypass security controls and gain full control over affected systems. Exploitation requires interaction with the ActiveReports.NET library, but the exact attack vector may vary depending on how the library is integrated into applications. The CVSS v3.0 base score is 9.8, reflecting the vulnerability's ease of exploitation (network accessible, no privileges or user interaction required) and its severe impact on confidentiality, integrity, and availability. Although no public exploits have been reported yet, the high severity and nature of the flaw make it a prime target for attackers once exploit code becomes available. Organizations using Mescius ActiveReports.NET 18.1.1 in their software stack should consider this a critical threat and prioritize remediation.

For European organizations, the impact of this vulnerability could be severe. ActiveReports.NET is a reporting tool used in various enterprise applications for generating reports and visualizing data. Successful exploitation could allow attackers to execute arbitrary code remotely, potentially leading to full system compromise, data theft, or disruption of critical business processes. This could affect confidentiality of sensitive data, integrity of reports and business logic, and availability of services relying on the reporting component. Given the critical nature of the vulnerability and the lack of required authentication or user interaction, attackers could target exposed services or internal applications that process untrusted data through ActiveReports.NET. This poses a significant risk to sectors such as finance, healthcare, manufacturing, and government agencies across Europe that rely on these reporting tools for decision-making and compliance. Additionally, the ability to execute code remotely could facilitate lateral movement within networks, increasing the scope of potential damage.

1. Immediate upgrade: Organizations should promptly update to a patched version of Mescius ActiveReports.NET once it becomes available. Since no patch links are currently provided, closely monitor vendor advisories for updates. 2. Input validation: Until a patch is available, implement strict input validation and sanitization on all data passed to the ReadValue method or any deserialization routines involving ActiveReports.NET. Reject or sanitize any untrusted serialized data. 3. Network segmentation: Restrict network access to services using ActiveReports.NET to trusted internal networks only, minimizing exposure to external attackers. 4. Application hardening: Employ application-level controls such as sandboxing or running the reporting service with least privilege to limit the impact of potential exploitation. 5. Monitoring and detection: Deploy intrusion detection/prevention systems and monitor logs for unusual deserialization activity or unexpected process behavior related to ActiveReports.NET components. 6. Incident response readiness: Prepare to respond quickly to any signs of exploitation by having forensic and remediation plans in place. 7. Vendor engagement: Engage with Mescius support to obtain early patches or mitigation guidance and report any suspicious activity.