CVE-2026-28732
Slash command trigger-word update allowed command hijacking
Vexday Risk Score
13Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 4.3EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch referenciado
Lifecycle
18 May 2026Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Affected products
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https://mattermost.com/security-updates