CVE-2026-6343

published 2026-05-18

CVE-2026-6343: Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check public/private permissions which allows members without these…

Priority P4 22 medium 4.3 CVSS 3.1

AV N AC L PR L UI N S U C L I N A N

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check public/private permissions which allows members without these permissions to access public playbooks via /get.. Mattermost Advisory ID: MMSA-2026-00591

Affected

10 ranges

Vendor	Product	Version range	Fixed in
github.com	mattermost_mattermost-plugin-playbooks	>= 0 < 1.41.1-0.20260309184833-887d9cacb616	1.41.1-0.20260309184833-887d9cacb616
github.com	mattermost_mattermost_server_v8	>= 10.11.0 < 10.11.14	10.11.14
github.com	mattermost_mattermost_server_v8	>= 11.4.0 < 11.4.4	11.4.4
github.com	mattermost_mattermost_server_v8	>= 11.5.0 < 11.5.2	11.5.2
mattermost	mattermost	10.11.0 – 10.11.13	—
mattermost	mattermost	11.4.0 – 11.4.3	—
mattermost	mattermost	11.5.0 – 11.5.1	—
mattermost	mattermost_server	>= 10.11.0 < 10.11.14	10.11.14
mattermost	mattermost_server	>= 11.4.0 < 11.4.4	11.4.4
mattermost	mattermost_server	>= 11.5.0 < 11.5.2	11.5.2

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CWE-863