Heym SSRF in the MCP fetch-tools endpoint

high severity · published 2026-11-11

Any authenticated Heym user, even with the lowest role, can make the server fetch an attacker-chosen URL with no scheme, private-IP or redirect checks. The error response acts as a semi-blind SSRF oracle, letting an attacker probe internal network services and control outbound request headers.

CVE: CVE-2026-67542

Source: NVD

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