Group prefix matching bypass for subscriptions_CVE-2026-6342

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 Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subscriptions to groups that were not whitelisted via creating groups that share the same prefix as a whitelisted group. Mattermost Advisory ID: MMSA-2026-00601

Basic Information

ID CVE-2026-6342

Source Mattermost

Published May 18, 2026 at 07:00

Affected Product

Vendor Mattermost

Product Mattermost

Affected Versions Mattermost Mattermost 0
Mattermost Mattermost 0
Mattermost Mattermost 0

CWE Classification

CWE-863

References

mattermost.com /security-updates

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    "published": "2026-05-18T07:00:24.969Z",
    "modified": "2026-05-18T07:00:24.969Z",
    "type": "cve",
    "title": "Group prefix matching bypass for subscriptions",
    "source": "Mattermost",
    "references": "https://mattermost.com/security-updates",
    "id": "CVE-2026-6342",
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