@cyclonedx/cyclonedx-npm: Shell Injection via Unsanitized --workspace Argument

Summary

A command injection vulnerability exists in @cyclonedx/cyclonedx-npm when the CLI is invoked with the --workspace option while the environment variable npm_execpath is unset or empty.
User‑supplied --workspace values are passed to a subshell without proper sanitization, enabling attackers to inject arbitrary OS commands.
This issue corresponds to CWE‑78: Improper Neutralization of Special Elements used in an OS Command.

The vulnerability was fixed in version 5.0.0.

Vulnerability Details

When cyclonedx-npm is executed with the --workspace option, the provided argument is incorporated into an internal shell command.
If the environment variable npm_execpath is set, the tool uses the npm executable directly and no injection occurs.
However, when npm_execpath is unset or empty, the tool falls back to spawning a subshell and interpolating the --workspace value directly into the command string without proper escaping or neutralization.

As a result, specially crafted workspace names can break out of the intended command context and execute arbitrary commands with the privileges of the invoking user.

Impact

An attacker who can influence the value passed to --workspace can execute arbitrary OS commands.
This may lead to:

• Arbitrary command execution
• Data exfiltration
• Local privilege escalation (depending on how the tool is used)
• Modification or destruction of files accessible to the user running the CLI

The vulnerability affects only scenarios where:

• The user invokes cyclonedx-npm with --workspace , and
• The environment variable npm_execpath is unset or empty

Exploitation Conditions (High‑Level)

Exploitation requires the attacker to supply or influence the --workspace value passed to the CLI.
If the tool falls back to its subshell execution path, specially crafted workspace identifiers can cause unintended command execution.
No exploit code is included here to avoid providing weaponizable examples.

Root Cause

The CLI constructs a shell command using untrusted input from the --workspace option.
Because the fallback code path does not sanitize or escape the workspace value, special shell metacharacters (e.g., ;, &&, |) are interpreted by the shell, enabling command injection.

This behavior matches CWE‑78.

Fix

The vulnerability was resolved in PR #1476, which ensures that workspace values are handled safely and are no longer passed to a subshell in an unsafe manner.

The fix is included in @cyclonedx/cyclonedx-npm version 5.0.0.

Remediation

• Upgrade to version 5.0.0 or later, which contains the complete fix.
• As a temporary mitigation for older versions, ensure that the environment variable npm_execpath is set before invoking the tool.
• Avoid passing untrusted or user‑controlled values to the --workspace option.