Quote from: Manfred Macx on December 23, 2016, 08:32:03 AM

This isn't the only source of malleability. The abandoned BIP62 lists ways in which a Bitcoin transaction is malleable:

Non-DER encoded ECDSA signatures
Non-push operations in scriptSig
Push operations in scriptSig of non-standard size type
Zero-padded number pushes
Inherent ECDSA signature malleability
Superfluous scriptSig operations
Inputs ignored by scripts
Sighash flags based masking

Of course. I have already said it was an "umbrella term" to which amacilin picked one and I specifically gave him a solution to that. I also mentioned hashing the final stack which would fix:

Superfluous scriptSig operations
Inputs ignored by scripts
Sighash flags based masking
Non-push operations in scriptSig

The DER encoding is a consensus issue since OpenSSL accepts BER and DER (DER being a subset of BER). Pre-checking before passing to OpenSSL is trivial.

The point is that malleability is an edge case symptom that can be solved without adding a lot more complexity. There is a lot more to this SegWit proposal than we are being told.