CVE-2026-28732

4.3 MEDIUM

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during ...

Published: 2026-05-18 · Last updated: 2026-05-19

Severity and scoring

CVSS: 4.3 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CWE: CWE-863

Affected products

Vendor	Product
mattermost	mattermost_server

Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during command updates which allows an authenticated team member with Manage Own Slash Commands permission to hijack and impersonate existing system or custom slash commands via editing their own slash command trigger to an already-registered trigger through the command update API. Mattermost Advisory ID: MMSA-2026-00597

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2026-28732
[Vendor advisory]https://mattermost.com/security-updates

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