CVE-2026-93856 (CVSS 4.3)

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.

Is your site exposed to CVE-2026-93856?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

EPSS — Exploit Prediction

0.0037

Probability of exploitation

0.31%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-669 CWE-669

References

Other References

https://bugs.launchpad.net/cinder/+bug/2160671 https://security.openstack.org/ossa/OSSA-2026-045.html https://www.openwall.com/lists/oss-security/2026/10/20/17 http://www.openwall.com/lists/oss-security/2026/10/20/17 https://bugs.launchpad.net/cinder/+bug/2160671

Frequently Asked Questions

What is CVE-2026-93856? +

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. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2026-93856? +

CVE-2026-93856 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0037, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-93856? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-48831

Wine ships a .desktop file that registers itself as a MIME handler for EXE files and several other Windows executable …

CVE-2026-40552

mpGabinet is vulnerable to Remote Command Execution. An authorized user with access to the application and direct access to the …

CVE-2025-67895 9.8

Edge3 Worker RPC RCE on Airflow 2. This issue affects Apache Airflow Providers Edge3: before 2.0.0 - and only if …

CVE-2026-20194 9.1

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Identity Services Engine (ISE) and Cisco …

CVE-2025-41645 8.6

An unauthenticated remote attacker could use a demo account of the portal to hijack devices that were created in that …

CVE-2025-34158 8.5

Plex Media Server (PMS) 1.41.7.x through 1.42.0.x before 1.42.1 is affected by incorrect resource transfer between spheres because /myplex/account provides …

CVE-2026-93856