CVE-2026-16046 PUBLISHED

Missing run-state validation on finished playbook runs

Assigner: Mattermost
Reserved: 17.07.2026 Published: 17.08.2026 Updated: 17.08.2026

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to enforce run-state validation on write operations for finished playbook runs which allows a run participant to modify status, checklists, retrospective content, ownership, and participants on completed runs via REST and GraphQL API requests. Mattermost Advisory ID: MMSA-2026-00675

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS Score: 3.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	Low	Integrity Impact	Low
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	Mattermost
Product	Mattermost
Versions	Default: unaffected affected from 11.7.0 to 11.7.6 (incl.) affected from 10.11.0 to 10.11.21 (incl.) Version 11.9.0 is unaffected Version 11.7.7 is unaffected Version 10.11.22 is unaffected

Solutions

Update Mattermost to versions 11.9.0, 11.7.7, 10.11.22 or higher.

Credits

ilent0 finder

References

MMSA-2026-00675

Problem Types

CWE-863: Incorrect Authorization CWE