Volerion logoVolerion
Volerion logoVolerion

Mattermost Access Control Vulnerability in Thread Reading via AI Posts

Vulnerability

A vulnerability exists in Mattermost versions 10.5.x prior to 10.5.9, where the application fails to properly validate access controls at the time of access. This flaw allows users to read threads through AI-generated posts, potentially exposing private or sensitive conversations.

Impact

Exploitation of this vulnerability could lead to unauthorized access to thread content, allowing users to read posts they should not have access to.

Remediation

Users can upgrade to Mattermost version 10.5.9 or later to address this vulnerability.

Added: Aug 21, 2025, 8:19 AM
Updated: Aug 21, 2025, 8:19 AM

Vulnerability Rating

Custom Algorithm
spread
3.1
impact
2.5
exploitability
5.0
remediation
7.7
relevance
0.4
threat
0.0
urgency
2.9
incentive
1.7

Our algorithm analyzes dozens of metrics to generate these 8 key vulnerability categories, which are then combined to calculate the overall risk score.