Cyber Posture

CVE-2026-23744

CriticalPublic PoC

Published: 16 January 2026

Published
16 January 2026
Modified
13 March 2026
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.3224 96.9th percentile
Risk Priority 39 60% EPSS · 20% KEV · 20% CVSS

Description

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

Security Summary

CVE-2026-23744 is a remote code execution (RCE) vulnerability affecting MCPJam inspector, a local-first development platform for MCP servers, in versions 1.4.2 and earlier. The flaw, linked to CWE-306 (Missing Authentication for Critical Function), arises when a crafted HTTP request triggers the unintended installation of an MCP server, enabling RCE. By default, MCPJam inspector binds to 0.0.0.0 rather than 127.0.0.1, exposing the service to remote networks. The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity.

Any unauthenticated remote attacker can exploit this vulnerability by sending a simple crafted HTTP request to the exposed MCPJam inspector instance. Successful exploitation grants arbitrary code execution on the target system with the privileges of the inspector process, potentially leading to full system compromise, data theft, or further lateral movement.

The patch is available in version 1.4.3 of MCPJam inspector. Official advisories and the fixing commit are detailed in the GitHub security advisory (GHSA-232v-j27c-5pp6) and the patch commit (e6b9cf9d9e6c9cbec31493b1bdca3a1255fe3e7a), recommending immediate upgrade to mitigate the issue.

Details

CWE(s)
CWE-306

Affected Products

mcpjam
inspector
≤ 1.4.3

AI Security Analysis

AI Category
AI Agent Protocols and Integrations
Risk Domain
Protocol-Specific Risks
OWASP Top 10 for LLMs 2025
None mapped
MITRE ATLAS Techniques
None mapped
Classification Reason
Matched keywords: mcp, mcp

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

The vulnerability enables unauthenticated remote code execution via crafted HTTP requests to the exposed MCPJam inspector service (binding to 0.0.0.0), directly facilitating T1190: Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References