CVE-2026-6517 — Mattermost Desktop App fails to restrict the allow list of domains which NTLM credentials are passed
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 …
Published: 2026-06-15 · CVSS: 6.3 · CVSS 3.1
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
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7