RCE in Cfdude Mac-Shell-Mcp
CVE-2026-108953
mac-shell-mcp before 2.0.0 contains an OS command injection vulnerability that allows MCP clients to bypass the command whitelist by injecting shell metacharacters into execute_command arguments. Attackers or malicious prompts can call a safe command such as pwd with arguments like ';' to run forbidden commands as the server user without approval.
Vulnerability class: Command Injection (OS Command Injection)
Published .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/cfdude/mac-shell-mcp/issues/45 (issue-tracking)
- github.com/cfdude/mac-shell-mcp/commit/932ce733cde07bb30b1f186303e6692dbb5d087a (patch)
- github.com/cfdude/mac-shell-mcp/blob/1c1708201abb7a18c83075e1bf933e7a92cbeb9f/s… (technical-description)
- github.com/cfdude/mac-shell-mcp (product)
- www.vulncheck.com/advisories/mac-shell-mcp-before-2.0.0-os-command-injection-vi… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-108953?
- CVE-2026-108953 is a high-severity vulnerability in Cfdude Mac-Shell-Mcp, classified under OS Command Injection. CVSS score: 7.8/10. Published 2026-10-12.
- How severe is CVE-2026-108953?
- High severity. CVSS v3 base score is 7.8 out of 10.