Signal offers to validate public keys of contacts via a separate channel (QR codes) to detect MITM attacks. The second claim is that the ciphers used are outda

Signal offers to validate public keys of contacts via a separate channel (QR codes) to detect MITM attacks. The second claim is that the ciphers used are outdated. A counter-claim that can be made here is that signal relies on well established and widely used methods which ensures that any significant weaknesses are more likely to be found. So far there are none that result in practical attacks.