CVE-2025-41064 identifies an improper authentication vulnerability (CWE-287) in GTT's OpenSIAC product, specifically version 1.0. OpenSIAC integrates with Cl@ve, a Spanish government-backed authentication system widely used for accessing public services online. The vulnerability allows an attacker to bypass authentication controls and impersonate legitimate users without needing any prior authentication or user interaction. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H) indicates that the attack can be performed remotely over the network with low complexity and no privileges or user interaction required. The impact on confidentiality, integrity, and availability is high, as attackers can gain unauthorized access to sensitive personal and governmental data, potentially manipulate records, or disrupt services. Although no public exploits have been reported yet, the critical severity rating and the nature of the flaw make it a prime target for threat actors aiming to compromise identity verification systems. The vulnerability stems from incorrect implementation of authentication logic within OpenSIAC's integration with Cl@ve, failing to properly verify user credentials or session tokens. This flaw undermines trust in the authentication process and exposes users and organizations to identity theft, fraud, and unauthorized data access.

For European organizations, especially public sector entities and service providers relying on OpenSIAC and Cl@ve for identity verification, this vulnerability poses a severe risk. Attackers exploiting this flaw can impersonate legitimate users, leading to unauthorized access to sensitive personal data, government services, and critical infrastructure. This can result in data breaches, fraudulent transactions, disruption of public services, and erosion of citizen trust in digital government platforms. The impact extends beyond confidentiality to integrity and availability, as attackers might alter records or disrupt authentication services. Given Cl@ve's prominence in Spain and its adoption in other EU countries for e-government services, the threat could affect a wide user base. Additionally, the vulnerability could be leveraged for large-scale identity fraud campaigns or targeted attacks against high-value individuals or institutions. The absence of known exploits currently provides a window for proactive mitigation, but the critical severity demands immediate attention to prevent exploitation.

Organizations should prioritize patching OpenSIAC to a fixed version once GTT releases an update addressing CVE-2025-41064. Until patches are available, restrict network access to OpenSIAC services using firewalls and network segmentation to limit exposure to trusted IP ranges. Implement additional layers of authentication beyond Cl@ve, such as multi-factor authentication (MFA), to reduce the risk of impersonation. Conduct thorough audits of authentication logs to detect anomalous access patterns indicative of exploitation attempts. Educate users and administrators about the vulnerability and encourage vigilance for suspicious activity. Collaborate with national cybersecurity agencies like INCIBE for guidance and threat intelligence sharing. Review and strengthen identity verification workflows to include out-of-band verification methods where feasible. Finally, prepare incident response plans specifically addressing potential identity impersonation scenarios to enable rapid containment and remediation.