[HN Gopher] Breaking RAR5 and 7Zip Passwords
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Breaking RAR5 and 7Zip Passwords
Author : cyberlab
Score : 30 points
Date : 2021-04-07 12:24 UTC (10 hours ago)
(HTM) web link (blog.elcomsoft.com)
(TXT) w3m dump (blog.elcomsoft.com)
| mcraiha wrote:
| Does anyone know if the Legacy (Zip 2.0) requires same password
| to encrypt and decrypt? Or is the password hashed so there are
| multiple possible passwords that can decrypt the same content.
|
| Because I remember that I used some .zip password breaking tool
| in summer of 2004 to decrypt one tutorial video. The tool gave a
| password (something like dabngrgj3) and it worked for that
| tutorial video. But it didn't work for other tutorial video .zip
| packages in that same site.
| shuggard2 wrote:
| There is no hash. The zipping process at a high level works as
| follows ...
|
| 1) File(s) are compressed and a CRC32 is generated.The Checksum
| is placed in the header. 2) The file body is encrypted but the
| CRC32 is not. 3) A user tries to unzip and supplies a password.
| Irrespective of whether the password is correct or not the zip
| is decompressed and the Checksum is compared against the value
| in the header.
|
| So there is no separate password for encryption/decryption like
| you ask.
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(page generated 2021-04-07 23:02 UTC)