DVWA: Insecure Captcha Vulnerability Solution (LOW Security)
CAPTCHA (Computer Automated Public Turing test to tell Computers and Humans apart) is used to determine whether or not the user is human. It is useful for Protecting against authentication related attacks, Avoiding SPAM and DOS, Protection against bots that do data mining etc.
In this case, it is possible to bypass captcha by performing second step directly i.e. modifying step parameter to 2.