CVE-2026-93856
MEDIUMDescription
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.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 31% of all known CVEs.
References
Related Vulnerabilities
Other CWE-669 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2026-31431 | Medium | 5.5 | 98% | KEV | Fix |
| CVE-2002-0055 | Medium | 5.0 | 38% | - | - |
| CVE-2026-25253 | High | 8.8 | 32% | - | Fix |
| CVE-2020-1048 | High | 7.8 | 17% | - | - |
| CVE-2021-22900 | High | 7.2 | 14% | KEV | - |
| CVE-2020-6862 | Medium | 5.3 | 6.3% | - | - |
Common questions
How do I fix CVE-2026-93856?
Upgrade cinder on debian unstable to 2:29.0.0-3 or later.
Is CVE-2026-93856 being actively exploited?
Not that we know of. CVE-2026-93856 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.37% is the estimated probability that it will be exploited in the next 30 days. That is higher than 31% of all scored CVEs.
How severe is CVE-2026-93856?
CVE-2026-93856 has a CVSS v3 base score of 4.3, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-93856 affect?
Published advisories record a fix for cinder (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
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Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-10-22.