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Unable to recover keys from nested ZIP archives compressed with Deflate #161

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@sanqiaixiayu

Hello,
I found that when a ZIP archive is compressed again using the Deflate method and then encrypted with ZipCrypto, it is not possible to recover the encryption keys using the original file as known plaintext.
The program shows the following error:
[23:52:20] Z reduction using 1048569 bytes of known plaintext
0.3 % (3549 / 1048569)
[23:52:20] Attack on 1 Z values at index 1045029
100.0 % (1 / 1)
[23:52:20] Could not find the keys.
However, if the compression method is changed to Store (no compression), the keys can be recovered successfully.
Is there any workaround or solution for this issue?
Thank you.

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