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by wk2jkhkjdfglsl 3074 days ago
Not exactly because bitcoin only supports a few simple transaction types -- Pay to Public Key, Pay to Public Key Hash ('standard tx'), Pay to Script Hash, Pay to Public Key Witness Hash, Pay to Script Witness Hash.

These are only serial dependent -- ie: A pays B, B pays C. You cannot reorder and still remain valid.

The security of the standard tx is the strength of the public key hash function RIPEMD-160. The security of Pay to Script Hash is finding a valid SHA256 collision with OPCODES.

The witness variants are a new tx format that uses less space (aka segwit).

The attack is simply a Denial of service, an attacker can block a tx. So if A pays B was never included in a block, B could never pay C.