CVE-2026-6342 | THREATINT

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

PUBLISHED Reserved 2026-04-15 | Published 2026-05-18 | Updated 2026-05-18 | Assigner Mattermost

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

Problem types

CWE-863: Incorrect Authorization

Product status

Default status

unaffected

Any version

affected

Any version

affected

Any version

affected

11.6.0

unaffected

11.5.2

unaffected

10.11.14

unaffected

11.4.4

unaffected

Credits

eahmed finder

References

mattermost.com/security-updates (MMSA-2026-00601) vendor-advisory

cve.org (CVE-2026-6342)

nvd.nist.gov (CVE-2026-6342)

Download JSON