A flaw in Consul allows an authenticated user to register or alter health checks belonging to services other than their own on the same node. The vulnerability can be exploited to manipulate the perceived health status of a service, potentially misleading traffic routing or load‑balancing decisions. The weakness is an authorization bypass (CWE‑639) that affects confidentiality and integrity of cluster configuration.

HashiCorp Consul Community Edition and Consul Enterprise are affected. All releases prior to Community Edition 2.1.0 and Enterprise versions before 2.1.0 or 1.21.19 are vulnerable. The issue is limited to nodes where the user can access the Consul API to register health checks.

The CVSS score of 6.4 indicates a medium impact. EPSS data is not available, but the vulnerability is not listed in CISA KEV, suggesting no publicly confirmed exploitation yet. The likely attack vector is an authenticated user with API access, which could be a local administrator or a remote user who has obtained credentials. An attacker can modify check parameters or fail checks to force a service to be marked healthy or unhealthy at will.