CVE-2026-93858

Severity: high (CVSS 8.7 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-08 · updated 2026-10-08
Weakness: CWE-78

Description

In OpenStack Mistral through 23.0.0, the std.ssh_proxied action passes a caller-supplied proxy_command value directly to paramiko.ProxyCommand() before any SSH connection to a gateway or target host is attempted. An authenticated project member can use the standard action-execution API to submit an arbitrary local command as proxy_command; paramiko starts that command as a subprocess on the executor host under the executor's own service account, independent of whether the SSH connection itself ever succeeds. Only Mistral deployments that permit the std.ssh_proxied action, the default configuration, are affected.

Affected products

OpenStack Mistral: before 20.1.1; from 21.0.0 before 21.0.1; from 22.0.0 before 22.0.1; 23.0.0 — fixed in 20.1.1, 21.0.1, 22.0.1

How to fix

Upgrade to a fixed version: OpenStack Mistral 20.1.1, 21.0.1, 22.0.1. Check the vendor advisory for mitigations.

References

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