January 27, 2023: Decrypting Salted Base64 of finance.yahoo.com using Google Apps Script

function myFunction() {
  // Load crypto-js.min.js.
  const cdnjs =
    "https://cdnjs.cloudflare.com/ajax/libs/crypto-js/4.1.1/crypto-js.min.js";
  eval(UrlFetchApp.fetch(cdnjs).getContentText());

  // Retrieve HTML and retrieve salted base64.
  const url = "https://finance.yahoo.com/quote/PGEN/press-releases"; // This is a sample URL.
  const html = UrlFetchApp.fetch(url)
    .getContentText()
    .match(/root.App.main = ([\s\S\w]+?);\n/);
  if (!html || html.length == 1) return;
  const tempObj = JSON.parse(html[1].trim());
  let obj;
  if (
    typeof tempObj.context.dispatcher.stores === "string" ||
    tempObj.context.dispatcher.stores instanceof String
  ) {
    // Decrypt the salted base64.
    const key = [
      ...new Map(
        Object.entries(tempObj)
          .filter(([k]) => !["context", "plugins"].includes(k))
          .splice(-4)
      ).values(),
    ].join("");
    if (!key) {
      throw new Error(
        "Specification at the server side might be changed. Please check it."
      );
    }
    obj = JSON.parse(
      CryptoJS.enc.Utf8.stringify(
        CryptoJS.AES.decrypt(tempObj.context.dispatcher.stores, key)
      )
    );
  } else {
    obj = tempObj.context.dispatcher.stores;
  }
  console.log(obj);
}