CVE-2025-15313 is a vulnerability identified in Tanium EUSS (Endpoint User Session Security) versions 1.17.0 and 1.18.0, categorized as an improper link resolution before file access, commonly known as a 'link following' vulnerability. This type of flaw occurs when the software fails to properly validate or resolve symbolic links before performing file operations, such as deletion. An attacker with local privileges can exploit this behavior to cause arbitrary file deletion by creating or manipulating symbolic links that the application follows, thereby deleting unintended files. The CVSS 3.1 base score is 5.5 (medium severity), with an attack vector of local (AV:L), low attack complexity (AC:L), requiring low privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), no confidentiality impact (C:N), high integrity impact (I:H), and no availability impact (A:N). This means the attacker must have some level of local access but can execute the attack without user interaction, leading to integrity compromise through unauthorized file deletion. The vulnerability does not affect confidentiality or availability directly but can disrupt system operations or cause data loss. No known exploits are currently reported in the wild, and no patch links are provided yet, indicating that remediation may be pending or in progress. Tanium EUSS is widely used for endpoint management and security in enterprise environments, making this vulnerability relevant for organizations relying on it for endpoint integrity and security posture.

For European organizations, the primary impact of CVE-2025-15313 is the potential for unauthorized deletion of critical files on endpoints managed by Tanium EUSS. This can lead to disruption of endpoint security functions, loss of important configuration or operational data, and increased risk of further compromise if security controls are impaired. Organizations in sectors such as finance, healthcare, manufacturing, and critical infrastructure that depend on Tanium for endpoint management may experience operational disruptions or require incident response efforts to restore integrity. Since exploitation requires local access and low privileges, insider threats or attackers who have already gained foothold on endpoints pose the greatest risk. The lack of confidentiality and availability impact reduces the risk of data breaches or denial of service, but integrity loss can still cause significant operational and compliance challenges, especially under strict European data protection and cybersecurity regulations. The absence of known exploits provides some time for organizations to prepare mitigations and patch once available.

1. Monitor Tanium's official channels for patches addressing CVE-2025-15313 and apply updates promptly once released. 2. Restrict local user privileges on endpoints to the minimum necessary, preventing unauthorized users from gaining the low-level access required to exploit this vulnerability. 3. Implement strict file system monitoring and alerting to detect unusual file deletions or symbolic link manipulations indicative of exploitation attempts. 4. Employ endpoint detection and response (EDR) tools to identify suspicious local activities related to file operations. 5. Conduct regular audits of user permissions and endpoint configurations to reduce the attack surface. 6. Educate internal teams about the risks of local privilege misuse and enforce policies to limit insider threats. 7. Consider network segmentation and access controls to limit lateral movement that could lead to local access on critical endpoints. 8. Prepare incident response plans that include scenarios involving integrity compromise through file deletion on managed endpoints.