I told my friend that PE Explorer is great Reverse Engineer tools, which include UPX unpacker plugin, can automatic unpack UPX pack files without failed
. but After my friend send me a modified Exe file which packed with UPX, asked me to open it with using PE Explorer, see how good PE explorer is
the PE Explorer is failed to unpacked it, the PE Explorer UPX unpacker plugin just detected the file is not a UPX-Packed.
Further checking the file with Ultraeditor, I realised that my friend who modified the Image header, Compress adler32, uncompress adler32, uncompress size, Compress size, Origin size, filter ID, CT0 and Link Checksum, he edit all those byte to zero.
after managed to try recovering the UPX image header, but I failed to do it. Just surrender to my friend.
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