OpenRemote Manager is vulnerable to a cross-tenant Insecure Direct Object Reference (IDOR) in the bulk alarm deletion endpoint. An authenticated user in any realm can delete alarms belonging to other realms (tenants) by supplying arbitrary alarm IDs. The vulnerability exists because the bulk removeAlarms() method only verifies that the caller's own realm is active and accessible, but never checks whether the targeted alarm IDs belong to the caller's realm before deleting them. This allows any user with alarm write permissions in their own realm to permanently destroy alarm records — including safety-critical and security alerts — belonging to any other tenant on the same OpenRemote installation. *** [Additional Information] The singular removeAlarm() method correctly validates that the target alarm's realm matches the caller's access: The plural removeAlarms() method is missing this per-alarm realm check and only validates the caller's own realm — a check that is trivially satisfied for any authenticated user: The underlying service queries contain no realm scoping: Alarm IDs are sequential auto-increment Long values (JPA @GeneratedValue), making them trivially enumerable. [Vulnerability Type] Insecure Direct Object Reference (IDOR) / Missing Authorization CWE-639: Authorization Bypass Through User-Controlled Key CWE-862: Missing Authorization *** [Vendor of Product] OpenRemote Inc. (openremote.io) *** [Affected Product Code Base] OpenRemote Manager - current version as of 2026 (github.com/openremote/openremote) *** [Affected Component] org.openremote.manager.alarm.AlarmResourceImpl#removeAlarms() org.openremote.manager.alarm.AlarmService#getAlarms(List<Long>) org.openremote.manager.alarm.AlarmService#removeAlarms() File: manager/src/main/java/org/openremote/manager/alarm/AlarmResourceImpl.java File: manager/src/main/java/org/openremote/manager/alarm/AlarmService.java *** [Attack Type] Remote (authenticated) *** [CVE Impact Other] Cross-tenant permanent destruction of alarm records, including safety-critical and security alerts in IoT environments. Also enables cross-tenant alarm enumeration (presence disclosure of alarm IDs across all tenants). *** [Attack Vectors] 1. Attacker registers or obtains any low-privilege account in any realm on the target OpenRemote installation (or uses an existing account). 2. Attacker enumerates alarm IDs belonging to other realms by sending bulk delete requests with sequential IDs (presence confirmed by 404 vs 200 response codes). 3. Attacker issues a single bulk delete request containing IDs of alarms belonging to victim realm(s). 4. Alarms are permanently deleted with no authorization error. PoC: <img width="1280" height="404" alt="image" src="https://github.com/user-attachments/assets/ffbebea2-2248-42a0-bb22-7a0dc51c78ce" />