CVE-2026-9820
Low
Description
Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671
SeverityLow
CVSS3.8
Exploit probability—
Product
Mattermost Server
PublishedJul 13, 2026
First seenJul 13, 2026
Weakness typeCWE-862Missing authorization
How to fix
Update
- mattermost mattermost_server10.11.20, 11.7.3 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost mattermost_server | 10.11.0 ≤ v < 10.11.20, 11.7.0 ≤ v < 11.7.3 | 10.11.20, 11.7.3 |
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