High 8.6Published Aug 25, 2026

CVE-2026-55580mcp-shell — Security Disabled by Default in Bare-Binary Deploy Path + Shell Interpreter in Secure-Mode Allowlist

Updated under an hour ago (2026-10-19 07:10 UTC)

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Every CVE for sonirico mcp-shell

Exploited in the last 30 days

mcp-shell is an MCP server for running shell commands securely, auditably, and on demand. Prior to 0.6.0, config.go initializes Security.Enabled to false, and when MCP_SHELL_SEC_CONFIG_FILE is unset, main.go starts the documented bare-binary deployment without a security policy. SecurityValidator.validateCommand in security.go then short-circuits and allows every command supplied to the shell_exec MCP tool, so an LLM connected over stdio can execute unrestricted OS commands as the mcp-shell process user. The README from-source installation and MCP client configuration omit MCP_SHELL_SEC_CONFIG_FILE, making the insecure state the documented default. This issue is fixed in version 0.6.0.

CVSS: 8.6 HIGH (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-78
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Aug 25, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

sonirico mcp-shell sonirico:mcp_shell (from the name)	before 0.6.0	CNA record

References

https://github.com/sonirico/mcp-shell/security/advisories/GHSA-f5pj-2738-996mx-refsource-confirm
https://github.com/sonirico/mcp-shell/pull/16x-refsource-misc
https://github.com/sonirico/mcp-shell/commit/f31377fce6ec31114e5a4398c0e5270552bce09fx-refsource-misc
https://github.com/sonirico/mcp-shell/releases/tag/v0.6.0x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.