https://cve.radiocsirt.org/rss/recent/all/10 Most recent entries from all 2026-10-08T06:17:44.990521+00:00 Vulnerability-Lookup csirt@opendfir.org python-feedgen Contains only the most 10 recent entries. https://cve.radiocsirt.org/vuln/cve-2026-4339 CVE-2026-4339 — SSRF via unvalidated attachment URLs in Mattermost Agents plugin MCP server 2026-10-08T06:17:44.991763+00:00

Affected: Mattermost

Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to validate attachment URLs against internal or private IP ranges in the Mattermost Agents plugin MCP server which allows an attacker with access to the MCP server in stdio mode to perform server-side request forgery (SSRF) and exfiltrate data from internal network services via supplying internal URLs as file attachments in post creation requests.. Mattermost Advisory ID: MMSA-2026-00635