OpenStack Mistral 23.0.0 std.ssh_proxied exec arbitrary SSH command
CVE-2026-93858 Published on October 8, 2026
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.
Vulnerability Analysis
CVE-2026-93858 is exploitable with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. Public availability of a proof of concept (POC) exploit exists for CVE-2026-93858. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity and availability.
Weakness Type
What is a Shell injection Vulnerability?
The software constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
CVE-2026-93858 has been classified to as a Shell injection vulnerability or weakness.
Affected Versions
OpenStack Mistral:- Before 20.1.1 is affected.
- Version 21.0.0 and below 21.0.1 is affected.
- Version 22.0.0 and below 22.0.1 is affected.
- Version 23.0.0 is affected.