Vulnerabilities

CVSS

6.3 Medium

Vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N

Risk score

50.4

Published

2026-06-15

Status

Published

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

Weaknesses

CWE-522

Coverage 1

vulnerability

Multiples vulnérabilités dans les produits Mattermost (22 mai 2026)

Multiple vulnerabilities have been discovered in Mattermost products, allowing an attacker to bypass security policies and potentially lead to an unspecified security issue. These vulnerabilities affect various versions…

CERT-FR · May 22, 2026 Medium

CVE-2026-5139CVE-2026-6062CVE-2026-6517vulnerabilitysecuritypatch

All articles mentioning it

Advisories and references

• mattermost.com/security-updates