CVE-2026-53521 Nezha Monitoring: Stored future DDNS profile ID allows unauthorized use of another user's DDNS profile context

Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 2.0.14 to before version 2.1.0, PATCH /server/id accepts and persists nonexistent ddnsprofiles IDs for a member-owned server. If another user later creates a DDNS profile with one of those...

CVE-2026-53521

CVE-2026-53521 affects Nezha Monitoring. From versions 2.0.14 up to before 2.1.0, PATCH /server/{id} accepts and persists nonexistent ddns_profiles IDs for a member-owned server. If another user later creates a DDNS profile with one of those IDs, the DDNS worker resolves the stored ID and dispatc...