NodeJS: decipher attachment - SOLVED To answer my own question above how to fully decipher attachment and display image. The image is now able to display. // PreDownload: Grabbing the url from previous step const { data } = await axios.get("https://cvws.icloud-content.com/M/M...", { responseType: 'arraybuffer' }); const iv = Buffer.alloc(16); // buffer alloc fills with zeros const key = Buffer.from(attachmentKey.slice(2), 'hex',); const decipher = crypto.createDecipheriv("aes-256-ctr", key, iv); decipher.setAutoPadding(false); // No Padding let decrypted = decipher.update(data); // if input is a buffer don't choose a encoding its ignored decrypted += decipher.final('base64'); // tried 'binary' & 'base64' // Write decode decrypted data into a buffer than write to file fs.writeFileSync("myImg.jpeg", Buffer.from(decrypted, 'base64'))

NodeJs: Decryption of Business Chat Attachment I've tried the NodeJS steps above but to no unveil. I'm not sure what I'm missing here. Although I'm unable to display the image. I'm confident that this is a decipher issue. // PreDownload: Grabbing the url from previous step const { data } = await axios.get("https://cvws.icloud-content.com/M/M...", { responseType: 'arraybuffer' }); const iv = Buffer.alloc(16); // buffer alloc fills with zeros const key = Buffer.from(attachmentKey.slice(2), 'hex',); const decipher = crypto.createDecipheriv("aes-256-ctr", key, iv); decipher.setAutoPadding(false); // No Padding let decrypted = decipher.update(data); // if input is a buffer don't choose a encoding its ignored decrypted += decipher.final('base64'); // tried 'binary' & 'base64' // Write decrypted data to myImg.jpeg fs.writeFileSync("myImg.jpeg", decrypted)