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Lab link. The application has used a blacklist for security, but if we upload the .htaccess file, we can allow any file extension we want on the server. The file with the .php extension does not work. We make changes to the POST /my-account/avatar request. Now we can upload files with .l33t extension. We change …

Lab link. In some systems, there may be more than one vulnerability, or we may continue with a different vulnerability in the continuation of one vulnerability. In this lab, we can upload files thanks to path traversal. In the lab, we are asked to access the file /home/carlos/secret. We create a php file to access …

Lab link. Blind SSRF occurs when an application can be encouraged to send a back-end HTTP request to a given URL, but the response from the back-end request is not returned in the application’s front-end response. Using Burp Collaborator we can create unique domains and send them as payloads to the application. We can monitor …

Lab link. We can perform SSRF attack with parameters vulnerable to open redirection. Our path redirecting request is “GET /product/nextProduct?currentProductId=4&path=”. We edit this request according to our payload and send it with the stockApi used in the check stock process.

Lab link. Another SSRF measure is Whitelist-Based. The application only allows entries that match a whitelist. The filter can search for a match inside the input. We bypass this filter by exploiting inconsistencies in URL parsing. We try to find an SSRF vulnerability in the check stock feature in the application. We try some SSRF …

Lab link. Blacklist-based management can be used as a precaution against SSRF attacks. Some applications can block IP and keywords such as localhost, admin, or 127[.]0[.]0[.]0[.]1. This method can be bypassed. We navigate the application and find where an HTTP request communicates with the API endpoint. This is the stock check section. With the stockApi …

Lab link. First, we check if redirect_uri has a defense against path traversal. Browse other pages. Requests are followed in the comments section of the blog page. window.location.href and postMessage() are used in the comment section. window.location.href contains the current URL of the browser. postMessage() function is used in WebExtension API to communicate messages between …

Lab link. Various methods can be used to prevent manipulation of the redirect_uri parameter, one of them is the whitelist method. However, suppose we manage to communicate with the external domain at another point in the system, for example through a directory traversal vulnerability. In that case, we can manipulate it and steal important tokens. …

Lab link. We log in and when we log out and log in again, we see that we can log in without entering any login information. We pass the “GET /auth?client_id” request to the repeater and experiment with the redirect_uri parameter. When we change the value of the redirect_uri parameter, we do not get an …

Lab link. The state parameter stores a unique unpredictable value that depends on the current session in the client application. The OAuth service should return exactly this value in the response along with the authorization code. The state parameter ensures that the request comes from the person who initiated the OAuth flow. The state parameter …