CVE-2026-8823
Last modified
CVE-2026-8823 is a low-severity vulnerability rated 3.8/10 on the CVSS scale. Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669. EPSS estimates a 0.23% chance of exploitation in the next 30 days.
Description
Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669
Metrics
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | >= 10.11.0, < 10.11.18 |
| Mattermost | Mattermost Server | >= 11.7.0, < 11.7.1 |
References
- https://mattermost.com/security-updatesVendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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