1. Home
  2. CVE Database
  3. CVE-2026-10085
MEDIUM · 5.4

CVE-2026-10085

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...

Vulnerability 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

CVSS Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW

Affected Products

VendorProductVersions
MattermostMattermost Server>= 10.11.0, < 10.11.20

Related Weaknesses (CWE)

CWE-862

References

FAQ

What is CVE-2026-10085?

CVE-2026-10085 is a vulnerability with a CVSS score of 5.4 (MEDIUM). 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...

How severe is CVE-2026-10085?

CVE-2026-10085 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-10085?

Check the references section above for vendor advisories and patch information. Affected products include: Mattermost Mattermost Server.