Timeline for Manipulate encrypted file: AES / ECB / PKCS5Padding
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 7, 2018 at 14:07 | comment | added | Maarten Bodewes♦ | Henrik, of course a reshuffled ECB encrypted plaintext will decrypt to something else. If you can create a valid zip stream is a separate question; it may be pretty tricky to do that. | |
| Nov 9, 2017 at 9:00 | comment | added | gusto2 | @henrik if you have power to modify the data, the samy way it is possible to uncompress , modify and compress back effectively creating a valid gzip | |
| Nov 9, 2017 at 1:47 | comment | added | zaph | Since the file is compressed and then encrypted re-shuffling the blocks will reshuffle the compressed data and that may not decompress correctly so there would be a lot of trial and error to pick a block that will correctly-compress. Not that it couldn't be done but that there is no direct mapping from the compressed block to text. | |
| Aug 11, 2017 at 16:14 | comment | added | henrik | Thanks for your response Maarten. I had already tried, what you mentioned: Shuffling, deleting and duplicating blocks. The reading program decrypted the file without error. But in this case the program goes on with the next step, which is the decompression of the gzip stream. And then it fails because the streams checksum crc32 doesn't match or the stream is corrupt in another way. Any suggestions on this? | |
| Aug 10, 2017 at 21:43 | history | answered | Maarten Bodewes♦ | CC BY-SA 3.0 |