@akoskm/create-mcp-server-stdio has Command Injection in MCP Server due to unsafe `exec` API

published 2025-09-08 14 mo ago modified 2026-06-17 4 mo ago also GHSA-3ch2-jxxc-v4xf , EUVD-2025-27167

cvss: 9.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits: 0; none known

@akoskm/create-mcp-server-stdio is an MCP server starter kit that uses the StdioServerTransport. Prior to version 0.0.13, the MCP Server is written in a way that is vulnerable to command injection vulnerability attacks as part of some of its MCP Server tool definition and implementation. The MCP Server exposes the tool `which-app-on-port` which relies on Node.js child process API `exec` which is an unsafe and vulnerable API if concatenated with untrusted user input. Version 0.0.13 contains a fix for the issue.

Patch / fix

fixed in 1 links 2

npm @akoskm/create-mcp-server-stdio 0.0.13

github.com/akoskm/create-mcp-server-stdio@48c26bb commit
github.com/akoskm/create-mcp-server-stdio#1 pull request

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 14 mo ago (2025-09-08)

Exploit prediction

1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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

Affected packages

ecosystem	package	affected	fixed in
npm	@akoskm/create-mcp-server-stdio	<0.0.13	0.0.13

Affected products

akoskm create-mcp-server-stdio

Classification

Weakness

CWE-78 Improper Neutralization of Special Elements used in an OS Command
CWE-77 Improper Neutralization of Special Elements used in a Command

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary