Slash command trigger-word update allowed command hijacking_CVE-2026-28732

4.3 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

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

Basic Information

ID CVE-2026-28732

Source Mattermost

Published May 18, 2026 at 08:35

Affected Product

Vendor Mattermost

Product Mattermost

Version 11.5.0

Affected Versions Mattermost Mattermost 11.5.0
Mattermost Mattermost 10.11.0
Mattermost Mattermost 11.4.0

CWE Classification

CWE-863

References

mattermost.com /security-updates

{
    "lastseen": "",
    "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",
    "published": "2026-05-18T08:35:40.393Z",
    "modified": "2026-05-18T08:35:40.393Z",
    "type": "cve",
    "title": "Slash command trigger-word update allowed command hijacking",
    "source": "Mattermost",
    "references": "https://mattermost.com/security-updates",
    "id": "CVE-2026-28732",
    "bulletinFamily": "",
    "cwe": [
        "CWE-863"
    ],
    "cvelist": null,
    "sourceData": "Mattermost Mattermost 11.5.0\nMattermost Mattermost 10.11.0\nMattermost Mattermost 11.4.0",
    "sourceHref": "",
    "cvss": {
        "score": 4.3,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Mattermost",
    "version": "11.5.0",
    "vendor": "Mattermost",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}