Wazuh is an open-source security platform providing unified XDR and SIEM protection for endpoints and cloud workloads. In versions 4.0.0 through 4.14.6, a malicious or man-in-the-middle enrollment manager can crash a Wazuh agent during enrollment by returning a malformed key response with fewer than four fields, causing a NULL pointer dereference. The  w_enrollment_process_agent_key()  routine splits the manager-provided key into four space-separated fields but does not verify that all fields are present before passing them to validators. Because OS_StrBreak() leaves missing trailing entries as NULL and OS_IsValidName() calls strlen() on its argument without a NULL check, a response such as  OSSEC K:'1'  reaches OS_IsValidName(NULL) and terminates the agent process. Since Wazuh permits enrollment against an unverified manager when no CA certificate is configured, an attacker operating a rogue manager or intercepting the enrollment flow can deterministically crash agents, resulting in denial of service. This issue is fixed in version 4.14.7.