OpenStack Aodh/Watcher up to 20.0.0/21.0.0/22.0.0 Alarm List API/Webhook Trigger Endpoint all_projects/project_id improper authorization

Summaryinfo

A vulnerability classified as very critical was found in OpenStack Aodh and Watcher up to 20.0.0/21.0.0/22.0.0. Affected is an unknown function of the component Alarm List API/Webhook Trigger Endpoint. Executing a manipulation of the argument all_projects/project_id can lead to improper authorization. This vulnerability appears as CVE-2026-76878. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in OpenStack Aodh and Watcher up to 20.0.0/21.0.0/22.0.0. It has been declared as very critical. This vulnerability affects an unknown function of the component Alarm List API/Webhook Trigger Endpoint. The manipulation of the argument all_projects/project_id with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In OpenStack Aodh before 22.0.1, the alarm list API bypasses project scoping when the all_projects query parameter is set to false. The API checks for the presence of the all_projects key rather than its value; a true value enforces the administrator-only policy, but a false value removes the key and skips the branch that normally restricts results to the caller's project. A non-admin user with the reader role can list alarms from all projects, exposing alarm actions containing trust webhook URLs, Heat signal endpoints, project IDs, and user IDs. The parameter can also be combined with a foreign project_id to target a specific project's alarms. A related concern is that OpenStack Watcher does not apply authorization to its webhook trigger endpoint. Any authenticated user who learns an audit's webhook URL, for example from this leaked Aodh alarm metadata, can start an EVENT audit and its associated action plan regardless of their own project or role. The webhook endpoint has lacked policy enforcement since its introduction in the Ussuri release (Watcher 4.0.0).

The advisory is shared for download at launchpad.net. This vulnerability was named CVE-2026-76878 since 08/20/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/20/2026). The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version 20.0.1, 21.0.1 or 22.0.1 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Cloud Software

Vendor

• OpenStack

Name

• Aodh
• Watcher

Version

• 20.0
• 21.0
• 22.0

License

• free

Website

• Vendor: https://www.openstack.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion