# CVE-2026-93856: cinder: In OpenStack Cinder through 29.0.0, cross-project information disclosure can occur in the Messages API

CVE-2026-93856 is fixed in cinder on 1 platform by DEBIAN-CVE-2026-93856 (version 2:29.0.0-3), released October 31, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-93856
- Priority: Routine
- CVSS: 4.3 (medium)
- EPSS: 0.0037
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 21, 2026

## Description

In OpenStack Cinder through 29.0.0, cross-project information disclosure can occur in the Messages API. A non-admin user with the project-scoped 'member' or 'reader' role making the Block Storage API v3.3 "List messages" call finds the non-expired user messages for other projects included in the response, resulting in the leakage of UUIDs of resources owned by other projects, in addition to the user message about the other projects' resources (which, by design, are sanitized generic messages). All Cinder deployments are affected.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | cinder Debian 14 | 2:29.0.0-3 | [DEBIAN-CVE-2026-93856](https://patchblox.com/security/data/fix/linux/debian-cve-2026-93856.md) | Oct 31, 2026 |

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Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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