ICSE / Wireshark final exercice : how to rebuilt the Pdf?

Question

Hi everyone, in the last exercise, I managed to rebuilt the pdf file and it is perfectly readable, however the md5 hash generated from it keeps on been wrong. Is there anything special to consider when rebuilding the file? My method for rebuilting it was to remove top an bottom part that are obviously not part of the pdf, and also the newline character at the end of the last line, then concatenate everything together with a cat command.&nbsp;Thanks in advance for any hint.&nbsp;

gwenael · Answer

Hi,How looks like the md5 hash of the file ?

julienberbach123 · Answer

Hi, it's for me c880fe58d8a3c5c6ac4a2f45112be054At last I though it is the newline character at the end of each chunk, but it also does not work.&nbsp;

gwenael · Answer

I also&nbsp; made the concatenate with cat command but I don’t remember to have remove anything before concatenating.

julienberbach123 · Answer

OK, so may I ask if you have just removed the bondary line, and left the rest before concatenation?&nbsp;--------------------------29c9b0d697280692^MContent-Disposition: form-data; name="fileToUpload"; filename="file.001"^MContent-Type: application/octet-stream^M^M%PDF-1.4^M%âãÏÓ^M3597 0 obj^M&lt;&lt; ^M/Linearized 1 ^M/O 3601 ^M/H [ 953 1837 ] ^M/L 20702285 ^M/E 62511 ^M/N 618 ^M/T 20630225 ^M&gt;&gt; ^Mendobj^M &nbsp;&nbsp;

gwenael · Answer

I didn’t remove the boundary line, if I remember well.I made the concatenation in one shot :cat file.001 file.002 file.003 file.etc &gt;&gt; file.pdf