CVE-2026-3109

Mattermost Plugins versions <=11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584

CVSS v3 2.2 LOW

2.2^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.7 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://mattermost.com/security-updates	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-26 17:16

Updated : 2026-06-17 10:43

NVD link : CVE-2026-3109

Mitre link : CVE-2026-3109

CVE.ORG link : CVE-2026-3109

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-754

Improper Check for Unusual or Exceptional Conditions

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