CVE-2026-9820
Last modified
CVE-2026-9820 is a low-severity vulnerability rated 3.8/10 on the CVSS scale. 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.
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
Metrics
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | >= 10.11.0, < 10.11.20 |
| Mattermost | Mattermost Server | >= 11.7.0, < 11.7.3 |
References
- https://mattermost.com/security-updatesVendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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