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.
Published: 2026-10-08
Score: 6 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Unauthorized access to private workflows via misassigned membership
Action: Patch if available
AI Analysis

Impact

The vulnerability in OpenStack Mistral up to version 23.0.0 allows a project that accepts a shared private workflow to create an additional membership in the name of a third project. The new membership is recorded with the accepting project’s ID rather than the original workflow owner, preventing the owner from seeing or deleting it. The third project can then accept the invalidated membership and read or execute the original owner’s private workflow. Only the accepting project can revoke the access, meaning the workflow owner is unable to control permissible access once the membership is created.

Affected Systems

OpenStack Mistral deployments running versions up to and including 23.0.0 are affected. The issue involves the workflow membership API and affects any projects that use shared private workflows.

Risk and Exploitability

The CVSS score of 6 indicates moderate severity, and EPSS is not available, so exploitation likelihood is not quantified. The vulnerability is not listed in the CISA KEV catalog. An attacker can exploit the flaw by creating or accepting shared workflows between projects, which can lead to unauthorized access and execution of private workflows without the owner’s awareness.

Generated by OpenCVE AI on October 9, 2026 at 03:09 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Check for and install any available OpenStack Mistral update that resolves the workflow membership issue
  • Restrict workflow sharing settings to prevent projects from accepting shared workflows unless explicitly approved by the owner
  • Regularly inspect workflow membership logs for unexpected entries and revoke any unauthorized memberships
  • Enforce explicit owner confirmation before new memberships are ultimately accepted

Generated by OpenCVE AI on October 9, 2026 at 03:09 UTC.

Tracking

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Advisories

No advisories yet.

History

Thu, 15 Oct 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Fri, 09 Oct 2026 00:15:00 +0000

Type Values Removed Values Added
Title Misassigned Workflow Membership Enables Unauthorized Access to Private Workflows in OpenStack Mistral openstack-mistral: mistral: workflow membership sub-delegation allows unauthorized access grant to private workflows
Weaknesses CWE-862
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}

threat_severity

Moderate

Thu, 08 Oct 2026 20:00:00 +0000

Type Values Removed Values Added
First Time appeared Openstack
Openstack mistral
Vendors & Products Openstack
Openstack mistral

Thu, 08 Oct 2026 19:15:00 +0000

Type Values Removed Values Added
Title Misassigned Workflow Membership Enables Unauthorized Access to Private Workflows in OpenStack Mistral

Thu, 08 Oct 2026 17:45:00 +0000

Type Values Removed Values Added
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.
Weaknesses CWE-863
References
Metrics cvssV4_0

{'score': 6, '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'}

Subscriptions

Openstack Mistral
cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-10-15T18:10:06.319Z

Reserved: 2026-09-18T19:15:59.203Z

Link: CVE-2026-93861

cve-icon Vulnrichment

Updated: 2026-10-15T16:16:59.220Z

cve-icon NVD

Status : Deferred

Published: 2026-10-08T18:18:31.153

Modified: 2026-10-15T19:17:49.017

Link: CVE-2026-93861

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-08T19:17:47Z

Links: CVE-2026-93861 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-10-09T03:15:15Z

Weaknesses