CVE-2026-2476: MS Teams plugin sensitive config values not properly masked in support packets

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-16 · updated 2026-06-17
Weakness: CWE-200

Description

Mattermost Plugins versions <=2.0.3.0 fail to properly mask sensitive configuration values which allows an attacker with access to support packets to obtain original plugin settings via exported configuration data. Mattermost Advisory ID: MMSA-2026-00606

Affected products

Mattermost Ms Teams: before 2.3.1 — fixed in 2.3.1

How to fix

Upgrade to a fixed version: Mattermost Ms Teams 2.3.1. Check the vendor advisory for mitigations.

References

https://mattermost.com/security-updates

Get alerted when CVE-2026-2476 or the next vulnerability affects your stack