CVE-2026-26304

4.3 mediumEPSS 0.2%

Medium (4.3) in mattermost mattermost server. EPSS 0.2% chance of exploitation in the next 30 days. Fixed in github.com/mattermost/mattermost-plugin-playbooks 1.41.1-0.20260316224925-705f54a81841.

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2 fail to verify run_create permission for empty playbookId, which allows team members to create unauthorized runs via the playbook run API. Mattermost Advisory ID: MMSA-2025-00542

Severity

CVSS 3.1

4.3 medium

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

EPSS: 0.2% chance of exploitation in the next 30 days; higher than 5% of CVEs (scores of 2026-10-31)
CWE: CWE-863
Published: 2026-03-16
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mattermost:mattermost_server

Packages (OSV)

Advisory	Ecosystem	Package	Affected	Fixed in
GHSA-4pmx-622h-x359	Go	github.com/mattermost/mattermost-plugin-playbooks	<1.41.1-0.20260316224925-705f54a81841	1.41.1-0.20260316224925-705f54a81841
GO-2026-4812	Go	github.com/mattermost/mattermost-plugin-playbooks	<1.41.1-0.20260316224925-705f54a81841	1.41.1-0.20260316224925-705f54a81841

References

https://mattermost.com/security-updates

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