CVE-2025-27936

Mattermost Plugin MSTeams versions <2.1.0 and Mattermost Server versions 10.5.x <=10.5.1 with the MS Teams plugin enabled fail to perform constant time comparison on a MSTeams plugin webhook secret which allows an attacker to retrieve the webhook secret of the MSTeams plugin via a timing attack during webhook secret comparison.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

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:ms_teams::::::::

History

14 Jan 2026, 14:29

Type	Values Removed	Values Added
Summary		(es) Las versiones <2.1.0 de Mattermost Plugin MSTeams y las versiones 10.5.x <=10.5.1 de Mattermost Server con el complemento MS Teams habilitado no pueden realizar una comparación de tiempo constante en un secreto de webhook del complemento MSTeams, lo que permite que un atacante recupere el secreto de webhook del complemento MSTeams a través de un ataque de tiempo durante la comparación del secreto de webhook.
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
First Time		Mattermost Mattermost mattermost Server Mattermost ms Teams
CPE		cpe:2.3:a:mattermost:mattermost_server:::::::: cpe:2.3:a:mattermost:ms_teams::::::::

16 Apr 2025, 10:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-04-16 10:15

Updated : 2026-01-14 14:29

NVD link : CVE-2025-27936

Mitre link : CVE-2025-27936

CVE.ORG link : CVE-2025-27936

JSON object : View

Products Affected

mattermost

mattermost_server
ms_teams

CWE

CWE-208

Observable Timing Discrepancy

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