PT-2025-42482 · Mattermost · Mattermost Desktop App

Doyensec · Published 2025-10-16 · Updated 2025-10-16 · CVE-2025-55035

Positive Technologies (AI Summary)

CVSS v3.1

6.1

Medium

Base vector

AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Mattermost versions prior to 5.13.0

Description The Mattermost Desktop App does not properly manage modals. This impacts users connecting to servers that utilize basic authentication, potentially preventing access. An attacker can provide a malicious server to a user, and upon configuration, force a modal popup that cannot be closed, effectively denying use of the Desktop App.

Recommendations Update to a version greater than 5.13.0.

Fix

DoS

Improper Check for Exceptional Conditions

Weakness Enumeration

CWE-754

Related Identifiers

CVE-2025-55035

Affected Products

Mattermost Desktop App

References · 5

• https://osv.dev/vulnerability/CVE-2025-55035 · Vendor Advisory
• https://mattermost.com/security-updates · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-55035 · Security Note
• https://t.me/CVEtracker/35099 · Telegram Post
• https://twitter.com/CVEnew/status/1978926596665810945 · Twitter Post