CVE-2026-6517

Published: Giu 15, 2026 Last Modified: Giu 15, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 6,3
Attack Vector: network
Attack Complexity: high
Privileges Required: low
User Interaction: none
Scope: changed
Confidentiality: high
Integrity: none
Availability: none

Description

AI Translation Available

Mattermost Desktop App versions <=6.1 5.5.13.0 fail to restrict the allow list of domains to which NTLM credentials were forwarded to in the Mattermost Desktop App which allows any user on a server without the image proxy enabled to intercept other users credentials via embedding an image that routes to an external web server. Mattermost Advisory ID: MMSA-2026-00651

522

Insufficiently Protected Credentials

Incomplete
Common Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Gain Privileges Or Assume Identity
Applicable Platforms
Technologies: Not Technology-Specific, Web Based, ICS/OT
View CWE Details
https://mattermost.com/security-updates