CVE-2026-50287 Missing Authentication for Critical Function in @agenticmail/mcp
Remote attackers can execute tools and access data via the unauthenticated /mcp endpoint when HTTP transport is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-50287?
CVE-2026-50287 is a high-severity missing authorization vulnerability in agenticmail, published on 12 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-306
Which versions are affected by CVE-2026-50287?
2 open source packages ship an affected version, including @agenticmail/mcp.
| Package | Affected | Fixed in |
|---|---|---|
@agenticmail/mcp npm | All versions | 0.9.27 |
@agenticmail/mcp npm | All versions | 0.9.27 |
How do I fix CVE-2026-50287?
Upgrade @agenticmail/mcp to 0.9.27 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-50287 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-50287 exists.
Sources
Also known as GHSA-63gr-g7jc-v8rg.