CVE-2026-75025 PUBLISHED

Mattermost Desktop local network access from server-rendered content

Assigner: Mattermost
Reserved: 17.08.2026 Published: 16.09.2026 Updated: 16.09.2026

Mattermost Desktop App versions <=6.2 6.2.2.0 Fixed an issue where Mattermost Desktop did not sufficiently restrict server-rendered content from accessing local or private network resources. Thanks to game0v3r for contributing to this improvement under the Mattermost responsible disclosure policy. Mattermost Advisory ID: MMSA-2026-00698

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
CVSS Score: 4.7

Attack Vector	Network	Scope	Changed
Attack Complexity	Low	Confidentiality Impact	Low
Privileges Required	None	Integrity Impact	None
User Interaction	Required	Availability Impact	None

CVSS 3.1

Product Status

Vendor	Mattermost
Product	Mattermost
Versions	Default: unaffected affected from 0 to 6.2.2 (incl.) Version 6.3.0 is unaffected Version 6.2.3.0 is unaffected

Solutions

Update Mattermost Desktop App to versions 6.3.0, 6.2.3.0 or higher.

Credits

game0v3r finder

References

MMSA-2026-00698

Problem Types

CWE-346: Origin Validation Error CWE