HashiCorp Vault CVE-2026-5051

Exploitation requires three concurrent conditions: (1) the attacker must possess high-privilege Vault credentials sufficient to configure audit devices - PR:H per the CVSS vector; (2) the Vault deployment must be using the legacy file audit path option for an audit device, which is a non-default configuration; and (3) the attacker must reach the Vault API over the network (AV:N), though AC:H indicates additional complexity in reliably triggering the bypass. Exploitation is limited by the need for high administrative privilege and the non-default legacy path option - environments that have never configured a legacy file audit device are not exposed. There is no user interaction required once these conditions are met.

The CVSS 3.1 score of 4.4 (Medium) reflects high attack complexity and high privilege requirements, which significantly constrain real-world exploitability. The vector AV:N/AC:H/PR:H confirms this is only reachable by an already-authenticated, highly privileged Vault operator over the network - not an opportunistic external attacker. The high confidentiality impact (C:H) is the most serious signal, suggesting that file contents outside the plugin directory could be exposed. EPSS data was not provided, and no KEV listing or public POC is present, which is consistent with the high barrier to exploitation. The practical risk is elevated primarily in environments where Vault admins are untrusted or where insider threat is a concern, and where the legacy file audit path option is in active use - a non-default condition. Overall, this is a real but narrowly exploitable privilege-escalation-adjacent path traversal: defenders should prioritize patching environments using the legacy audit path configuration and audit admin-level access to Vault.

A malicious or compromised Vault administrator authenticates to the Vault API with high-privilege credentials and creates or modifies a file audit device, supplying a path containing traversal sequences (e.g., '../../etc/passwd') via the legacy file audit path option. Because the plugin directory guard is not consistently enforced on this legacy code path, Vault processes the traversal, exposing file content outside the plugin directory. No public POC has been identified, but the attack primitive is straightforward for any actor with the required admin credentials.