Security issues with web applications
So far, we have seen four types of security issues with Python, namely, those with reading input, evaluating expressions, overflow errors, and serialization issues. All our examples so far have been with Python on the console.
However, almost all of us interact with web applications on a daily basis, many of which are written in Python web frameworks such as Django, Flask, Pyramid, and others. Hence, it is more likely that we are exposed to security issues in such applications. We will look at a few examples here.
Server Side Template Injection
Server Side Template Injection (SSTI) is an attack using the server-side templates of common web frameworks as an attack vector. The attack uses weaknesses in the way user input is embedded on the templates. SSTI attacks can be used to figure out internals of a web application, execute shell commands, and even fully compromise the servers.
We will see an example using a very popular web application framework in Python...