CVE-2025-64645 is a vulnerability classified under CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition) affecting IBM Concert versions 1.0.0 through 2.1.0. This flaw occurs when the software performs a security check on a file or symbolic link and then uses that file without re-verifying its state, allowing an attacker to exploit the time gap between these operations. Specifically, a local attacker can create or manipulate symbolic links to trick the application into performing privileged operations on unintended files, thereby escalating their privileges on the system. The vulnerability requires local access but no prior privileges or user interaction, making it easier for attackers who have limited access to elevate their rights. The CVSS v3.1 base score of 7.7 indicates a high severity due to the combination of local attack vector, low attack complexity, no privileges required, and no user interaction needed. The impact primarily affects confidentiality and integrity, as attackers can gain unauthorized access to sensitive data or system functions. Availability is not impacted. IBM Concert is an enterprise software product used for business process management and collaboration, often deployed in corporate environments. Although no public exploits are known yet, the nature of TOCTOU vulnerabilities makes them attractive targets for attackers aiming to bypass local security controls. The lack of available patches at the time of publication necessitates immediate mitigation efforts by affected organizations.

For European organizations, this vulnerability poses a significant risk of local privilege escalation, potentially allowing attackers to gain unauthorized administrative access. This can lead to unauthorized disclosure or modification of sensitive business data, disruption of business processes, and compromise of system integrity. Organizations in sectors such as finance, manufacturing, and critical infrastructure that rely on IBM Concert for workflow and collaboration are particularly vulnerable. The ability to escalate privileges locally can facilitate further lateral movement within networks, increasing the risk of broader compromise. Given the high CVSS score and the absence of required user interaction, the threat is substantial even in environments with restricted user permissions. The impact is heightened in environments where IBM Concert is integrated with other critical enterprise systems, as attackers could leverage escalated privileges to access additional resources. European data protection regulations, such as GDPR, also increase the consequences of data breaches resulting from such vulnerabilities, potentially leading to regulatory penalties and reputational damage.

1. Immediately restrict local user permissions to the minimum necessary, preventing untrusted users from accessing IBM Concert installation directories or related file systems where symbolic links could be manipulated. 2. Implement file system monitoring and alerting for suspicious symbolic link creation or modification activities, using host-based intrusion detection systems (HIDS) or endpoint detection and response (EDR) tools. 3. Apply principle of least privilege to all users and processes interacting with IBM Concert to reduce the attack surface. 4. Segregate IBM Concert servers from general user workstations to limit local access opportunities. 5. Regularly audit and review file system permissions and symbolic link usage within the IBM Concert environment. 6. Monitor vendor communications closely and apply official patches or updates as soon as they become available. 7. Consider deploying application whitelisting or sandboxing techniques to limit the ability of unauthorized code execution or manipulation. 8. Educate system administrators about TOCTOU vulnerabilities and the importance of timely patching and monitoring. 9. If patching is delayed, consider temporary compensating controls such as disabling non-essential local accounts or restricting shell access on affected systems.