Unauthorized API Use in Mattermost 10.11-11.2 and Zoom Plugin <=1.11.0
CVE-2026-0998 Published on February 16, 2026
Mattermost Zoom Plugin allows unauthorized meeting creation and post modification via insufficient API access controls
Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 and Mattermost Plugin Zoom versions <=1.11.0 fail to validate user identity and post ownership in the {{/api/v1/askPMI}} endpoint which allows unauthorized users to start Zoom meetings as any user and overwrite arbitrary posts via direct API calls with manipulated user IDs and post data.. Mattermost Advisory ID: MMSA-2025-00534
Vulnerability Analysis
CVE-2026-0998 is exploitable with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity, and no impact on availability.
Weakness Type
What is an AuthZ Vulnerability?
The software does not perform an authorization check when an actor attempts to access a resource or perform an action.
CVE-2026-0998 has been classified to as an AuthZ vulnerability or weakness.
Products Associated with CVE-2026-0998
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Affected Versions
Mattermost:- Version 11.1.0, <= 11.1.2 is affected.
- Version 10.11.0, <= 10.11.9 is affected.
- Version 11.2.0, <= 11.2.1 is affected.
- Version 11.3.0 is unaffected.
- Version 11.1.3 is unaffected.
- Version 10.11.10 is unaffected.
- Version 11.2.2 is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.