01: 
The deletion of documents does not require authentication

02: 
In the given example, the authentication mechanism is implemented using Flask-HTTPAuth, which provides basic HTTP authentication. This type of authentication relies on the Authorization header with a base64-encoded username:password combination. The authentication is not broken per se, but it is not secure enough for production use because it only uses basic HTTP authentication, which is vulnerable to several types of attacks.

For instance, one way an attacker could access the endpoint without proper authentication is by intercepting the communication between the client and the server. If the connection is not encrypted (e.g., using HTTPS), the attacker could potentially read the Authorization header and obtain the base64-encoded username:password combination, decode it, and gain unauthorized access.

Another way an attacker could access the endpoint without proper authentication is by running a brute force attack. Since basic HTTP authentication relies on a simple username and password combination, an attacker could try a large number of username and password combinations to gain access. The given example does not include any protection mechanisms, such as rate limiting or account lockout, making it more susceptible to brute force attacks.

To protect your API from unauthorized access, you should implement more secure authentication mechanisms, such as OAuth 2.0 or JSON Web Tokens (JWT), and enforce HTTPS to encrypt the communication between the client and the server. Additionally, consider adding rate limiting, account lockout, and other security features to mitigate brute force and other types of attacks.

03: 
User can edit the blocked property even though they should not be able to

04:
There is no rate limiting

05:
There is a /login that lets you login just by entering the userID and if you enter 1, you get access to a list of users

06: 
This file simple saves a link without properly validating if it's even an image and executes the request

07:
We have 0 security headers being sent in the response such as 

    response.headers["Cache-Control"] = "no-store, no-cache, must-revalidate, max-age=0"
    response.headers["Pragma"] = "no-cache"
    response.headers["Expires"] = "0"

08:
We are lacking any sort of captcha or rate limiting here

09:
In this example, we have created two versions of a login API endpoint that accept an email and password. The first version, login_v1, simulates a login process without any security improvements. The second version, login_v2, simulates a login process with security improvements. However, the older version of the API (v1) is still accessible and doesn't receive the same security treatment as the newer version (v2). This increases the attack surface and leaves the API vulnerable to attackers who can exploit the less secure version of the login endpoint. Additionally, there is no proper inventory management or documentation to track these different versions and their security levels.

10:
In this example, we have created a simple Flask API that fetches a random quote from a third-party API and returns it to the client. The API is vulnerable because it does not:

Use a secure communication channel (TLS) to interact with the third-party API.
Validate and sanitize the data received from the third-party API before processing it or passing it to downstream components.
Handle redirections or implement any resource limits or timeouts for interactions with the third-party service.
This increases the risk of exposing sensitive information to unauthorized actors, as well as the possibility of various types of injection attacks. Proper security measures should be implemented to ensure the safe consumption of third-party APIs.