- CVSS
- HIGH · 7.8v3.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Published
- 2026-10-12
- Weakness
- CWE-78
- Source
- nvd.nist.gov/vuln/detail/CVE-2026-108953
Description
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.
References
- https://github.com/cfdude/mac-shell-mcp
- https://github.com/cfdude/mac-shell-mcp/blob/1c1708201abb7a18c83075e1bf933e7a92cbeb9f/src/services/command-service.ts#L257-L340
- https://github.com/cfdude/mac-shell-mcp/commit/932ce733cde07bb30b1f186303e6692dbb5d087a
- https://github.com/cfdude/mac-shell-mcp/issues/45
- https://www.vulncheck.com/advisories/mac-shell-mcp-before-2.0.0-os-command-injection-via-execute-command-arguments
How GTK Cyber trains on this
AI security training at GTK Cyber covers the LLM and ML-pipeline vulnerability classes that vulnerabilities like CVE-2026-108953 fall into. Our hands-on courses are taught by Charles Givre and other practitioners who break and defend production AI systems.