dbcve.org
Missing AuthenticationWeakness · CWE-306

CVE-2026-50287

HIGH · 8.7 CVSS v4.0 Published 2026-06-12
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
96/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

The @agenticmail/mcp package exposes a Streamable HTTP transport when launched with --http or MCP_HTTP=1. The /mcp endpoint accepts requests without any HTTP authentication, allowing remote attackers to initialize sessions and directly invoke exposed tools without credentials.

MitigationUpgrade to version 0.9.27 or later. Until patched, avoid using HTTP transport mode or implement upstream network-level access controls.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
Authentication
X
User interaction
None
Scope
X

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if @agenticmail/mcp is installed
    Run 'npm list @agenticmail/mcp' or check your package.json dependencies
    Affected if The package appears in your dependencies
  2. Determine the installed version
    Run 'npm list @agenticmail/mcp' to see the exact version number, then compare it to the affected range (versions prior to 0.9.27)
    Affected if The installed version is lower than 0.9.27
  3. Check if HTTP transport mode is enabled
    Inspect your startup command for the --http flag, or run 'env | grep MCP_HTTP' to check if the MCP_HTTP=1 environment variable is set
    Affected if Either --http flag is present or MCP_HTTP=1 environment variable is set to a truthy value
  4. Verify network exposure of the /mcp endpoint
    Review your network configuration, firewall rules, or reverse proxy settings to determine if the /mcp HTTP endpoint is accessible from outside your trusted network
    Affected if The HTTP transport is bound to a publicly accessible network interface or exposed without firewall protection

You are affected if @agenticmail/mcp version is below 0.9.27 AND the HTTP transport is enabled with the /mcp endpoint exposed to untrusted networks.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to version 0.9.27 or later. Until patched, avoid using HTTP transport mode or implement upstream network-level access controls.

Recommended fix High confidence

0.9.27 or later

  1. Upgrade @agenticmail/mcp to version 0.9.27 or later using your package manager (e.g., npm update @agenticmail/mcp or pip install --upgrade agenticmail-mcp)
  2. Verify the installed version matches 0.9.27 or later
  3. Restart the service with --http or MCP_HTTP=1 to ensure the patched version is running
  4. Test the /mcp endpoint to confirm authentication is now enforced

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-50287 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data