BloodHound versions up to 9.4.0 contain a missing authorization check in the custom‑nodes API endpoints. Any user authenticated with a valid session token can use unprotected POST, PUT, and DELETE operations on these endpoints to create, update, or delete custom node types, thereby altering the global graph schema used by all users and tenants. This change can compromise the integrity of modeling data and the overall network representation.

SpecterOps BloodHound, versions through 9.4.0. The vulnerability was fixed in commit 8f79035, which added authorization checks to the custom‑nodes API.

The CVSS score of 7.1 indicates a moderate to high risk, while the EPSS score of less than 1% suggests a low probability of exploitation at present. The vulnerability is not listed in CISA KEV. The likely attack vector requires a valid authenticated session token; attackers can exploit this vector by sending POST, PUT, or DELETE requests to the custom‑nodes endpoints, resulting in unauthorized changes to the global graph schema.