Improper Input Validation
Versions of the npm CLI prior to 6.13.3 are vulnerable to an Arbitrary File Write. It is possible for packages to create symlinks to files outside of thenode_modules folder through the bin field upon installation. A properly constructed entry in the package.json bin field would allow a package publisher to create a symlink pointing to arbitrary files on a user's system when the package is installed. This behavior is still possible through install scripts. This vulnerability bypasses a user using the --ignore-scripts install option.
CWE-20 - Improper Input Validation
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.