CVE-2026-5059: aws-mcp-server command injection in allowed commands list

Executive brief

aws-mcp-server is a tool used to interface with AWS services. A vulnerability in how it handles command lists allows an unauthenticated remote attacker to execute arbitrary code on the server. This could lead to a full system compromise, unauthorized access to AWS resources, and significant operational disruption.

Technical details

A command injection vulnerability exists in aws-mcp-server versions 1.7.0 and earlier due to improper neutralization of special elements used in OS commands (CWE-78). The flaw is located within the handling of the allowed commands list, where user-supplied strings are not properly validated before being passed to a system call. An unauthenticated remote attacker can exploit this by sending a specially crafted request to the server, resulting in arbitrary code execution in the context of the MCP server process. No patches are currently identified in the advisory.

Affected products

• Alexei Ledenev aws-mcp <= 1.7.0

Timeline

• 2026-04-11: disclosed
• 2026-04-11: advisory: GitHub Advisory published

References

• https://api.github.com/users/arnewouters
• https://github.com/arnewouters
• https://api.github.com/users/arnewouters/gists%7B/gist_id%7D
• https://api.github.com/users/arnewouters/repos
• https://avatars.githubusercontent.com/u/25950814?v=4
• https://api.github.com/users/arnewouters/events%7B/privacy%7D