HTB write up for the emdee five for life[EASY] challenge

lwlx

29 September 2021

@0x0000005

emdee five for life [EASY]

This is my Write Up for the "emdee five for life" challenge from Hack The Box.

challenge info

We get a website with encrypted data, this can be decrypted easily.

website

Ok so its clear we need to create a script to be able to decript and send a response fast enough..

const crypto = require("crypto");
const http = require("http");
const axios = require("axios").default;
const httpAgent = new http.Agent({ keepAlive: true });
 
const loadData = async () => {
  try {
    const response = await axios.get("http://144.126.206.242:32609", {
      httpAgent,
    });
 
    const PAGE = response.data;
    const x = "<h3 align='center'>";
    const y = "</h3>";
    const string = PAGE.substring(
      PAGE.indexOf(x) + x.length,
      PAGE.lastIndexOf(y)
    );
 
    console.log("recieved string: ", string);
    const md5 = (data) => crypto.createHash("md5").update(data).digest("hex");
    const hash = md5(string);
    console.log("new MD: ", hash);
 
    const response2 = await axios({
      method: "post",
      url: "http://127.0.0.1:32609",
      headers: {
        "Content-Type": "application/x-www-form-urlencoded",
        Cookie: "PHPSESSID=ilimcjsspls1p1qpnhlbdbf6o6",
      },
      data: `hash=${hash}`,
      //go through burp proxy
      proxy: {
        host: "127.0.0.1",
        port: 8080,
      },
      httpAgent,
    });
 
    console.log(response2.data);
  } catch (error) {
    console.error(error);
  }
};
 
loadData();

run the script:

node exploit.js