CVE-2025-10545
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-10-16

Last updated on: 2025-10-21

Assigner: Mattermost, Inc.

Description
Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when adding channel members which allows guest users to add any team members to their private channels via the `/api/v4/channels/{channel_id}/members` endpoint
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Meta Information
Published
2025-10-16
Last Modified
2025-10-21
Generated
2026-06-16
AI Q&A
2025-10-16
EPSS Evaluated
2026-06-14
NVD
CVE-2025-10545
EUVD
EUVD-2025-34728
Affected Vendors & Products
Showing 2 associated CPEs
Vendor Product Version / Range
mattermost mattermost_server From 10.5.0 (inc) to 10.5.11 (exc)
mattermost mattermost_server From 10.11.0 (inc) to 10.11.3 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-863 The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
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Executive Summary

This vulnerability exists in Mattermost versions 10.5.x up to 10.5.10 and 10.11.x up to 10.11.2, where guest users are not properly validated when adding members to channels. Specifically, guest users can add any team members to their private channels by exploiting the /api/v4/channels/{channel_id}/members endpoint, which should restrict such actions.

Impact Analysis

The vulnerability allows guest users to add any team members to their private channels, potentially exposing private communication channels to unauthorized users. This could lead to unauthorized access to sensitive information shared within private channels.

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