CVE-2026-76878 OpenStack CVE debrief

Who should care

Defenders responsible for OpenStack Aodh and Watcher deployments should assess exposure and verify remediation. They should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. Additionally, they should plan vendor-supported updates or mitigations through normal change control where exposure is confirmed and review compensating controls for exposed systems while remediation is scheduled and verified

Why it matters

CVE-2026-76878 allows non-admin users to list alarms from all projects in OpenStack Aodh, exposing sensitive metadata and potentially allowing unauthorized access to OpenStack Watcher webhook trigger endpoints.

• Non-admin users can list alarms from all projects, exposing sensitive metadata.
• Authenticated users can start EVENT audits and associated action plans using leaked webhook URLs.
• Defenders must verify and remediate OpenStack Aodh installations to prevent unauthorized alarm list exposure.
• OpenStack Watcher webhook trigger endpoints lack authorization, allowing unauthorized access.

Technical summary

The OpenStack Aodh alarm list API bypasses project scoping when the all_projects query parameter is set to false, allowing non-admin users to list alarms from all projects. This exposes sensitive metadata and potentially allows unauthorized access to OpenStack Watcher webhook trigger endpoints. The vulnerability affects OpenStack Aodh before 22.0.1 and OpenStack Watcher, which lacks authorization for its webhook trigger endpoint. To exploit this vulnerability, an attacker would need to be a non-admin user with the reader role and have access to the alarm list API.

Defensive priority

Defenders should prioritize verifying and remediating OpenStack Aodh installations to prevent unauthorized alarm list exposure.

Recommended defensive actions

• Verify OpenStack Aodh installations for the presence of the all_projects query parameter and restrict access to the alarm list API.
• Implement proper authorization for OpenStack Watcher webhook trigger endpoints.
• Review and update OpenStack Aodh and Watcher configurations to ensure proper scoping and access controls.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record and NVD entry provide details on the OpenStack Aodh vulnerability, including its description and potential impact. The vulnerability allows non-admin users to list alarms from all projects, exposing alarm actions containing trust webhook URLs, Heat signal endpoints, project IDs, and user IDs. OpenStack Watcher webhook trigger endpoints lack authorization, allowing unauthorized access.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.