CVE-2026-5163

Published: Mag 18, 2026 Last Modified: Mag 18, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 6,5
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: none
Availability: none

Description

AI Translation Available

Mattermost versions 11.5.x <= 11.5.1 fail to verify channel membership when processing AI-assisted message rewrites which allows an authenticated attacker to read the content of threads in private channels and direct messages they do not have access to via a crafted request to the post rewrite endpoint.. Mattermost Advisory ID: MMSA-2026-00645

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0004
Percentile
0,1th
Updated

EPSS Score Trend (Last 2 Days)

862

Missing Authorization

Incomplete
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Access Control Availability
Potential Impacts:
Read Application Data Read Files Or Directories Modify Application Data Modify Files Or Directories Gain Privileges Or Assume Identity Bypass Protection Mechanism Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Dos: Resource Consumption (Other)
Applicable Platforms
Technologies: AI/ML, Web Server, Database Server, Not Technology-Specific
Likelihood of Exploit: High
View CWE Details
Application

Mattermost Server by Mattermost

Product Information
Vendor Mattermost
Product Mattermost Server
Version Range Affected
From 11.5.0 (inclusive)
To 11.5.2 (exclusive)
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://mattermost.com/security-updates
https://mattermost.com/security-updates