Improper Neutralization of Special Elements used in a Command ('Command Injection')
An attacker could use the format parameter to inject arbitrary commands in the NPM package "morgan" before 1.9.1.
CWE-77 - Command Injection
A command injection attack involves injecting an operating system command through the data input, which gets executed on the host operating system with the privileges of the victimized application. The impact of a command injection attack may range from loss of data confidentiality and integrity to unauthorized remote access to the hosting system. The attack may cause serious data breaches and system takeover.