# CVE-2026-10085: Ordinary group/direct message member can enable group_constrained and remove all channel participants

> CVE-2026-10085: Ordinary group/direct message member can enable group_constrained and remove all channel participants. CVSS 5.4 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-10085
Last updated: 2026-07-14T13:19:08Z

- Published: 2026-07-13 08:05 UTC · Updated: 2026-07-14 13:19 UTC · Assigner: Mattermost
- CVSS: 5.4 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
- EPSS: 0.29%, 21th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-862

## Description

Mattermost versions 11.7.x \<= 11.7.2, 11.6.x \<= 11.6.4, 10.11.x \<= 10.11.19 fail to restrict the group\_constrained channel flag to public and private channels that support group synchronization, which allows an ordinary group or direct message member to remove all participants from the conversation via the channel patch API.. Mattermost Advisory ID: MMSA-2026-00688

## Affected vendors and products

- Mattermost: Mattermost

## Tracked companies

- [Mattermost](https://rewindex.com/company/mattermost.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-10085)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-10085)
- [https://mattermost.com/security-updates](https://mattermost.com/security-updates)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-10085 · Markdown: https://rewindex.com/cve/CVE-2026-10085.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-10085 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:00:59.610Z