Vulnerability · Published Feb 16, 2026 · Assigned by Mattermost

CVE-2026-0998Mattermost Zoom Plugin allows unauthorized meeting creation and post modification via insufficient API access controls

Medium 4.3

In plain English

A medium-severity missing authorization in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.3Medium
Exploit odds (30 days)0.2%top 92.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/mattermost/mattermost-plugin-zoom1.12.0GHSA-w65c-fvp5-fvc5
Gogithub.com/mattermost/mattermost-plugin-zoom1.12.0GO-2026-4525

Affected products (as reported)

VendorProductVersions
Mattermost Mattermost 11.1.0 – through 11.1.210.11.0 – through 10.11.911.2.0 – through 11.2.1

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

References