CVE-2026-28732 (GCVE-0-2026-28732)
Vulnerability from cvelistv5 – Published: 2026-05-18 08:35 – Updated: 2026-05-18 14:37
VLAI
EPSS
VEX
Title
Slash command trigger-word update allowed command hijacking
Summary
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
Severity
4.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-18 14:37 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://mattermost.com/security-updates | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Mattermost | Mattermost |
Affected:
11.5.0 , ≤ 11.5.1
(semver)
Affected: 10.11.0 , ≤ 10.11.13 (semver) Affected: 11.4.0 , ≤ 11.4.3 (semver) Unaffected: 11.6.0 Unaffected: 11.5.2 Unaffected: 10.11.14 Unaffected: 11.4.4 |
guessed |
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