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.

Severity (CVSS 4.0)8.7High
Exploit odds (30 days)0.4%top 70.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

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

EcosystemPackageFixed inAdvisory
npm@agenticmail/mcp0.9.27GHSA-63gr-g7jc-v8rg

Affected products (as reported)

VendorProductVersions
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

References