CVE-2026-8823 - Vulnerability Details - OpenCVE

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

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required High

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact Low

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products

References

Link	Providers
https://mattermost.com/security-updates

History

Mon, 22 Jun 2026 17:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 22 Jun 2026 15:45:00 +0000

Type	Values Removed	Values Added
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
Title		User Manager can demote bot accounts to guest without bot-management permission
Weaknesses		CWE-863
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 3.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-06-22T13:41:28.404Z

Updated: 2026-06-22T16:12:31.350Z

Reserved: 2026-05-18T10:05:31.691Z

Link: CVE-2026-8823

Vulnrichment

Updated: 2026-06-22T16:12:26.753Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-06-22T17:00:06Z

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