Shadow Era Cheats Games for PC, Mobile, iPhone, iPad. Hence, it is possible to put HTML encoded javascript inside the script tags and execute the payload using the showMessage popup.The Official Home of DJ Shadow. This means the HTML parser converts the HTML entities back to characters since it's not the HTML context anymore. On the right side instead, the part included in the SVG tag is not in the HTML context anymore but in SVG. As far as I understand it, please correct me if I’m wrong, everything is in the HTML context and the HTML entities are handled as we would expect it. The left one shows the DOM without the SVG tag. If you wonder why the application behaves this way, take a look at the two DOM trees below. Putting alert(1) in the sanitizer returns correctly sanitized output ( alert(1)), nevertheless, the javascript is executed anyway. Nevertheless, I found a working payload with which it is possible to bypass the sanitizer using, or better said, it is possible to execute javascript via even with the sanitized output. However, if we put the basic alert(1) payload in the sanitizer, it returns alert(1). Executed in the console of the website, the popup will display the Xs we set in allowedNumbers. The following code snippet sets the input length to 3000. This is probably due to an overflow in the wasm file however, I did not reverse the wasm file, so I don’t know the exact cause. Then, I played around with various inputs and the password length and eventually recognized that some of the input was reflected back when the password length is big enough. But besides that the password stays the same, it has no benefit. As a result, the password is always the same. The first thing I tried was to change the seed parameter. Next, we could try to escape the JSON and include other keys. If we now set to 123\nImNotADigit and call the generate function, we should theoretically see the check running through, resulting in differing variables length-1 and length-2.ĭamn, not so fast… Every time we try to set the value, the newline character disappears because the HTML input field allows no newline by default.Īs we can see above, the fix works. This is due to the multiline parameter in the regex string: "123\nImNotADigit".match(/^\d+$/gm) -> Array "123\nImNotADigit".match(/^\d+$/g) -> null Unfortunately, the check is invalid and can be bypassed by inserting a newline character. The regex check in line 11 analysis whether the password length only consists of digits or not. This means the password length in the JSON (length-1) and the one later used (length-2) could differ. However, it is already copied in the JSON before the check and manipulation in lines 11 to 14. It is further used in malloc to allocate bytes for the generated password. The output we get is the generated password and is contained in the parameter password.įirst, we analyze the parameter passwordLength, since it seems more relevant than the other parameters. All three parameters are included in the JSON string, which is later handed over as option parameter to the function generate_password. We can see that there are three input parameters: passwordLength, allowNumber, and allowSymbols. This function takes the output, sanitizes it, and displays it as a popup message. ![]() When the user generates a new password, the wasm file is called, and its output is passed on to the function showMessage. Passgen contains a password generator mainly implemented in a web assembly (wasm) file called program.wasm. Looking at the challenge’s website, we can see that an iframe is embedded, loading its content from /passgen.php. No self-XSS or man in the middle is allowed, and it should work for the latest Firefox or Chrome version. Therefore I hope a lot of people appreciate this writeup and take something from it.Īs for every Intigriti XSS challenge, the goal was to execute an alert(document.domain)on the given domain. ![]() At the time of writing this article, on the last day of the challenge, only 14 out of 22 submissions were accepted. In the following writeup, I go through my thinking process and explain my approach. Since I had some free time, I decided to give it a try. While scrolling through my Twitter feed, I saw a new post from Intigriti - a fresh XSS Challenge.
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