CryptoJS encrypt in aes-256-cbc returns an unexpected value

Question

I am encrypting some data using CryptoJS and comparing it to an online tool and I am not getting the same result. In fact the result from CryptoJS in not decryptable with the tool.

I am trying to encrypt in AES-256-CBC with the following parameters:

text = '111222333'
iv = 'I8zyA4lVhMCaJ5Kg'
key = '6fa979f20126cb08aa645a8f495f6d85'

Here's my code:

let text = '111222333';

aesEncrypt(data) {
    let key = '6fa979f20126cb08aa645a8f495f6d85';    //length 32
    let iv = 'I8zyA4lVhMCaJ5Kg';                     //length 16
    let cipher = CryptoJS.AES.encrypt(data, key, {
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    return cipher.toString();
}

aesEncrypt(text);

The resulting encrypted string is U2FsdGVkX1+f3UywYmIdtb50bzdxASRCSqB00OijOb0= while the one obtained with the online tool is B6AeMHPHkEe7/KHsZ6TW/Q==. Why are they different, I seem to be using the same parameters?

My plan in using CryptoJS is to encrypt some data client side and then be able to decrypt it server side, if needed. But the differences in both encrypted values is stopping me to do so.

Answer 1

How 'bout encoding your data as UTF-8. Just like the "online tool" is doing.

Use CryptoJS.enc.Utf8.parse to achieve what I'm saying.

aesEncrypt (data) {
   const key = '6fa979f20126cb08aa645a8f495f6d85'
   const iv = 'I8zyA4lVhMCaJ5Kg'
   
   const cipher = CryptoJS.AES.encrypt(data, CryptoJS.enc.Utf8.parse(key), {
       iv: CryptoJS.enc.Utf8.parse(iv), // parse the IV 
       padding: CryptoJS.pad.Pkcs7,
       mode: CryptoJS.mode.CBC
   })
   
   // e.g. B6AeMHPHkEe7/KHsZ6TW/Q==
   return cipher.toString()
}

Code snippet using CryptoJS.

function aesEncrypt (data) {
   const key = '6fa979f20126cb08aa645a8f495f6d85'
   const iv = 'I8zyA4lVhMCaJ5Kg'
   const cipher = CryptoJS.AES.encrypt(data, CryptoJS.enc.Utf8.parse(key), {
       iv: CryptoJS.enc.Utf8.parse(iv),
       padding: CryptoJS.pad.Pkcs7,
       mode: CryptoJS.mode.CBC
   })

   return cipher.toString()
}

// e.g. B6AeMHPHkEe7/KHsZ6TW/Q==
console.log(aesEncrypt('111222333'))

<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/rollups/aes.js"></script>

Working Stackblitz example