Vulnerability · Published Jun 12, 2026 · Assigned by GitHub_M
CVE-2026-50287Missing Authentication for Critical Function in @agenticmail/mcp
High 8.7
In plain English
A high-severity missing authentication in agenticmail from agenticmail. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
AgenticMail gives AI agents real email addresses and phone numbers. Prior to version 0.9.27, @agenticmail/mcp exposes a Streamable HTTP transport when started with --http or MCP_HTTP=1. In that mode, the /mcp endpoint accepts requests without any HTTP authentication layer. A remote client can initialize a session and call tools directly. This issue has been patched in version 0.9.27.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @agenticmail/mcp | 0.9.27 | GHSA-63gr-g7jc-v8rg |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| agenticmail | agenticmail | < 0.9.27 |
Weakness: CWE-306 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N