Transaction Malleability in the blockchain How does a transaction malleability look like in the blockchain? Are there any examples?
Here is example: https://blockchain.info/tx/683f45578328242a06bc5c54acbcbe6e70a5435b4561fc8b0570a59ab09f8bfa?show_adv=true

Look at first input script in raw:

4d49003046022100847361c694421bf63ea1b51d8e2189805b161ab3d4cb96ab745a20468dd6c2ea0221009160897652bedfd7c837855d793c32509063338ac7524b8f09abfed761cf16fc014d410004c8dde23708932059bf4491c96794c5412b1182d62d2741e0986cb87276d3053f0b7326155114ad67c04adc60b5a47718fa8744ecb86a001f99da8761113edb24


Look at first byte: 4d (OP_PUSHDATA2). It means, that next 2 bytes contains length of data, that will be pushed to stack. This length = 0x49. But typical transaction does not use OP_PUSHDATA2 command. If transaction was created by bitcoin-qt, it starts with length of data directly:

[4d]49[00]3046....


I take into brackets unnecessary bytes.

So, someone added 2 bytes to signature script, but did not break signature and changed id of transaction. Original tx was deleted from blockchain.info. Next link no longer works: https://blockchain.info/tx/ef74c1cbf0003fc4e96a87a59838f7dd3da488d9d83fec3f270b0d3d7c2bc309?show_adv=true

Look at wiki for more information about scripts: https://en.bitcoin.it/wiki/Script