CVE-2026-16046

MediumCVSS 4.3

Published: 17/08/2026(UTC)Updated: 18/08/2026(UTC)Translated: 18/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.15%

5th percentile - higher than 5% of all known CVEs

Summary

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.

Risk Assessment

The risk includes unauthorized modification of completed playbook runs, potentially leading to integrity compromise of processes and data.

Recommendation

Upgrade Mattermost to a version that fixes this vulnerability (as per vendor recommendations).

Original NVD description (English source)

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