Server-side Request Forgery (SSRF) Affecting auth-fetch-mcp package, versions <3.0.2
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- published4 Jul 2026
- disclosed1 Jul 2026
- creditUnknown
Introduced: 1 Jul 2026
NewCVE-2026-49857 (opens in a new tab)How to fix?
Upgrade auth-fetch-mcp to version 3.0.2 or higher.
Overview
auth-fetch-mcp is a MCP server that lets AI read Notion, Google Docs, Jira & any login-protected page via a real browser
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) in the isPrivateV6 function, which fails to properly detect IPv4-mapped IPv6 loopback addresses in their hex-normalized form. An attacker can access internal network services and retrieve sensitive information by supplying specially crafted URLs that bypass address validation.