CVE-2026-86348

Mattermost versions <=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

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)

OR	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::

History

14 Oct 2026, 19:28

Type	Values Removed	Values Added
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
First Time		Mattermost Mattermost mattermost Server
CPE		cpe:2.3:a:mattermost:mattermost_server::::::::

Information

Published : 2026-09-14 14:17

Updated : 2026-10-14 19:28

NVD link : CVE-2026-86348

Mitre link : CVE-2026-86348

CVE.ORG link : CVE-2026-86348

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-704

Incorrect Type Conversion or Cast

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