Basic Access Authentication, commonly called Basic Auth, is an authentication mechanism where the credentials are supplied, in base64 encoded form, in the request header, in this format:

Authorization: Basic [base64 encoded credentials]

Creating Your Basic Auth Header

Online tools exist which take your credentials as input, and output a basic auth header.  Just search for basic auth header generator or something similar. 

Alternatively, on Linux or Mac you can generate the header localy using the Command Line Interface (CLI):

echo "Authorization: Basic $(echo -n 'myusername:mypassword' | base64)"

where myusername is your username and mypassword is your password.

The output will be something like this:

Authorization: Basic bXl1c2VybmFtZTpteXBhc3N3b3Jk

Adding The Header To Your AppCheck Scan

Note: If your application uses both Basic Access Authentication and another authentication mechanism you can use the basic auth header in conjunction with a GoScript to authenticate with both systems.

The basic auth header should be added in:

Web Application Scanner Settings

-> HTTP Headers

-> Custom HTTP Headers

for example: