basic-ftp is an FTP client for Node.js. Versions prior to 5.3.0 are vulnerable to denial of service through unbounded memory growth while processing directory listings from a remote FTP server. A malicious or compromised server can send an extremely large or never-ending listing response to "Client.list()", causing the client process to consume memory until it becomes unstable or crashes. Version 5.3.0 fixes the issue.