CVE-2026-8683

MEDIUM

Overly long URLs crash the Mattermost Desktop App

Title source: cna
STIX 2.1

Description

Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a malicious server owner to crash the application via including a script to call window.open on a very large URL. Mattermost Advisory ID: MMSA-2026-00652

References (1)

Core 1
Core References
Vendor Advisory vendor-advisory
MMSA-2026-00652
https://mattermost.com/security-updates

Scores

CVSS v3 6.5
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-770
Status published
Products (3)
Mattermost/Mattermost < 5.5.13
Mattermost/Mattermost 5.13.6.0
Mattermost/Mattermost 6.2.0
Published Jun 15, 2026
Tracked Since Jun 15, 2026