PT-2025-46948 · Mattermost · Teams (Msteams) Plugin+1

Juho Forsén

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Published

2025-10-15

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Updated

2025-11-20

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CVE-2025-55073

CVSS v2.0

5.5

Medium

VectorAV:N/AC:L/Au:S/C:N/I:P/A:P
Name of the Vulnerable Software and Affected Versions Mattermost versions 10.5.x through 10.5.11 Mattermost versions 10.11.x through 10.11.3 Mattermost versions 10.12.x through 10.12.0
Description The Mattermost application does not properly validate the relationship between a post being updated and the Microsoft Teams (MSTeams) plugin OAuth flow. This allows an attacker to modify any post by using a specially crafted MSTeams plugin OAuth redirect URL. The issue involves a failure to validate the connection between the post update and the OAuth process.
Recommendations Update Mattermost to a version later than 10.5.11. Update Mattermost to a version later than 10.11.3. Update Mattermost to a version later than 10.12.0.

Fix

Improper Access Control

Missing Authentication

Weakness Enumeration

Related Identifiers

BDU:2025-16014
CVE-2025-55073
GHSA-FF85-QW3H-G9VP
GO-2025-4129

Affected Products

Mattermost
Teams (Msteams) Plugin