CVE-2026-53520 Details

A vulnerability exists in Nezha Monitoring versions 2.0.14 prior to 2.1.0, allowing authenticated users to claim the dashboard's Host through NAT management. This action can disrupt normal dashboard operations by preempting all routing for the claimed Host. The issue arises because the NAT management API is accessible to all authenticated users, not just administrators, and there are no checks to prevent claiming the dashboard's own Host. Exploitation can lead to a denial-of-service condition or unauthorized routing of dashboard requests through the attacker's selected agent.

To address this vulnerability, Nezha Monitoring should implement checks to prevent ordinary NAT profiles from claiming dashboard-owned Hosts. This can be done by rejecting NAT domain values that match the dashboard's public Host or any administrator-reserved domains. Additionally, consider making NAT domain creation require admin approval or verifying domain ownership for the requesting user.