Vulnerability · Published Oct 8, 2026 · Assigned by mitre
CVE-2026-93861
Medium 6.0
In plain English
A medium-severity incorrect authorization in Mistral from OpenStack. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | mistral | no fix listed | DEBIAN-CVE-2026-93861 |
| Debian:13 | mistral | no fix listed | DEBIAN-CVE-2026-93861 |
| Debian:14 | mistral | 23.0.0-2 | DEBIAN-CVE-2026-93861 |
| Ubuntu:22.04:LTS | mistral | no fix listed | UBUNTU-CVE-2026-93861 |
| Ubuntu:24.04:LTS | mistral | no fix listed | UBUNTU-CVE-2026-93861 |
| Ubuntu:26.04:LTS | mistral | no fix listed | UBUNTU-CVE-2026-93861 |
| Ubuntu:26.10 | mistral | no fix listed | UBUNTU-CVE-2026-93861 |
Affected products (as reported)
Weakness: CWE-863 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N