The link I provided discusses this as well; not only are there other attacks, but those other attacks are potentially more severe. A man-in-the-middle attacker

The link I provided discusses this as well; not only are there other attacks, but those other attacks are potentially more severe. A man-in-the-middle attacker can claim credit for a message by substituting their own signature for the sender's. A naive encrypt-then-sign system will also lack non-repudiation in some cases (e.g. when using RSA signatures and encryption), and will only provide non-repudiation on the ciphertext itself (not the plaintext; this may or may not be what you want).