Impact

The import-in-the-middle loader works by generating a wrapper module on the fly. The wrapper uses the module specifier to load the original module and add some wrapping code. It allows for remote code execution in cases where an application passes user-supplied input directly to an import() function.

Patches

This vulnerability has been patched in import-in-the-middle version 1.4.2

Workarounds

• Do not pass any user-supplied input to import(). Instead, verify it against a set of allowed values.
• If using import-in-the-middle and support for EcmaScript Modules is not needed, ensure that none of the following options are set (either via command-line or the NODE_OPTIONS environment variable):

--loader=import-in-the-middle/hook.mjs
--loader import-in-the-middle/hook.mjs

References

If you have any questions or comments about this advisory, email us at security@datadoghq.com