Description

An argument injection issue in the diff scan operation in AWS security-agent-mcp-server before version 0.2.0 might allow context-dependent threat actors to create, overwrite, or truncate arbitrary files on the host outside the intended workspace directory via a crafted reference value supplied to the diff scan operation. To remediate this issue, users should upgrade to version 0.2.0.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.2",
  "pubDate": "2026-10-01T18:17:29.230Z",
  "pubdate": "2026-10-01T18:17:29.230Z",
  "executiveSummary": "The AWS security-agent-mcp-server is susceptible to an argument injection vulnerability during diff scan operations, identified in versions prior to 0.2.0. This security flaw originates from improper input sanitization of the reference value provided to the diff scan function, which is subsequently passed to system-level commands.\nA threat actor can exploit this vulnerability by injecting malicious arguments into the reference parameter. Successful exploitation allows for unauthorized file system operations, specifically the creation, overwriting, or truncation of arbitrary files on the host system outside of the defined workspace boundaries. This represents a significant security risk, as it grants an attacker the ability to manipulate system files, potentially leading to privilege escalation, arbitrary code execution, or service disruption depending on the target file context. The vulnerability requires the attacker to provide a specifically crafted input that the application processes without adequate validation, effectively breaking out of the intended operational directory. All users of affected versions are advised to upgrade to version 0.2.0 to remediate the underlying flaw.",
  "technicalDetails": "The vulnerability resides within the diff scan operation logic of the security-agent-mcp-server. The root cause is the insecure concatenation or shell-passing of user-supplied input into system command-line arguments. Specifically, the application fails to properly sanitize the 'reference' value parameter before it is interpreted by the underlying operating system as part of a command line execution chain.\nIn a typical attack flow, the adversary supplies a malicious string as the 'reference' parameter. Due to the lack of input validation or the use of insecure execution functions (such as those that invoke a shell or fail to treat arguments as discrete tokens), the system interprets parts of the attacker-supplied string as flags or options for the underlying command-line tool. By injecting command-line options that redirect output or specify destination paths (such as using redirection operators or flag-based file path overrides), the attacker can escape the intended sandboxed workspace directory.\nThe exploitation process follows these steps: 1. Identification of the endpoint or interface exposed by the security-agent-mcp-server that triggers the diff scan operation. 2. Crafting a malicious 'reference' string that contains whitespace, command-line argument delimiters (e.g., dashes), or file path traversal sequences. 3. Submission of this crafted input to the server. 4. The server-side process executes the scan command, wherein the shell or command-line parser treats the injected characters as legitimate directives rather than literal parameters. 5. The command executes with the permissions of the security-agent-mcp-server process, resulting in the desired file system modification.\nThe impact is a loss of file system integrity. Because the security-agent-mcp-server operates on the host, the attacker can target sensitive files, system configuration files, or other sensitive data structures that the server's process has permission to modify. This facilitates arbitrary file corruption or overwrite, potentially impacting system stability or enabling secondary exploitation vectors, such as modifying configuration files to introduce backdoors or redirect application flow.\nThis vulnerability affects versions of security-agent-mcp-server before 0.2.0. The exploitability is context-dependent, relying on the attacker having the ability to trigger the diff scan operation with user-supplied arguments."
}