SECURELYN

CVE-2026-23744

MCPJam inspector is the local-first development platform for MCP servers. Versions 1.4.2 and earlier are vulnerable to remote code execution (RCE) vulnerability, which allows an attacker to send a crafted HTTP request that triggers the installation of an MCP server, leading to RCE. Since MCPJam inspector by default listens on 0.0.0.0 instead of 127.0.0.1, an attacker can trigger the RCE remotely via a simple HTTP request. Version 1.4.3 contains a patch.

Scores

9.8
CVSS 9.8 out of 10, critical severity.
67.5%
EPSS 67.5% chance of exploitation in the next 30 days.

The facts

Published
16 January 2026
Last changed
17 June 2026
NVD status
Analyzed
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Affects
  • mcpjam inspector
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
67.5% chance of exploitation activity in the next 30 days (percentile 99).

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References