CVE-2026-93861: Openstack Mistral

Medium severity, CVSS 6.0. EPSS: 0.3% chance of exploitation in the next 30 days.

In OpenStack Mistral through 23.0.0, the workflow membership API lets a project that has accepted a share of another project's private workflow create a further membership naming a third project. The new membership row is created with its project_id defaulted to the accepting project rather than the original workflow owner, and thus the owner can neither see nor delete it. The third project can accept this membership (that it had not actually been granted by the owner), and then read and execute the owner's private workflow; only the accepting (not the owning) project can later revoke that access.

Affected products

• Openstack Mistral: before 20.1.1 (fixed in 20.1.1); from 21.0.0, before 21.0.1 (fixed in 21.0.1); from 22.0.0, before 22.0.1 (fixed in 22.0.1); version 23.0.0 only

Published 2026-10-08. Last modified 2026-10-08.