Modal Management Vulnerability in Mattermost Desktop App by Mattermost
CVE-2025-55035

6.1MEDIUM

Key Information:

Vendor

Mattermost
Status
Mattermost
Vendor
CVE Published:
16 October 2025

What is CVE-2025-55035?

The Mattermost Desktop App versions up to 5.13.0 contains a flaw in managing modal popups, particularly affecting users connecting to servers using basic authentication. An attacker can exploit this vulnerability by tricking users into configuring a malicious server, leading the application to display a persistent modal popup that prevents user interaction. This effectively denies users access to the application, posing significant usability concerns.

Affected Version(s)

Mattermost 0 <= 5.0.13

Mattermost 5.13.1.0

References

https://mattermost.com/security-updates

CVSS V3.1

Score:
6.1
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Doyensec
JSON
.