pouzitelny desifrovac ZIP souboru

[Michal Lukac]

>-----Original Message----- 
>From: Michal Grunt
>Sent: Wednesday, March 28, 2012 10:07 AM
>To: HW-news
>Subject: RE: pouzitelny desifrovac ZIP souboru

>Asi před deseti lety jsem také potreboval heslo do ZIP archivu a nasel jsem 
>program, který na to nesel hrubou silou, ale stacilo mit na disku jeden 
>soubor, který byl stejny jako v >archivu (většinou se něco najde pokud 
>nejde zrovna jenom o dokumenty) a on to nejak porovnal a rovnou vypadlo 
>heslo. Akorat nevim jak se to jmenovalo :-) Akorat je otázka, zda >je to 
>pouzitelny na dnesni ZIP (ZIP64, UTF-8, ruzne druhy sifrovani...). Tak 
>třeba patrat timto smerem.


asi treba hladat "known plaintext"

napr: zip key to vie... ale je to dost stare..

New Zip Key decrypts most of WinZip archives in less than an hour with our 
new SureZip™ Recovery
All versions of WinZip and PKZip are supported
Brute-Force, Xieve™, SureZip™, Known Plaintext or Dictionary attacks are 
used to recover the password
Additional user dictionaries support, case changes, multiple mistypes and 
other modifications for each dictionary word

SureZip™ Recovery decrypts Zip archives created with WinZip version 8.0 and 
earlier in less than an hour regardless of password used to protect it. At 
least 5 encrypted files are required in order to process the archive. 
Archives created with WinZip are supported.

Limitations
Zip compression software uses relatively strong encryption algorithm that 
makes instant password calculation (without knowing at least one file from 
the archive) impossible. Brute-force attack is the slowest approach and can 
test all the passwords of up to 8 characters. Xieve™ attack is much faster 
and is capable of recovering passwords of up to 10 characters. Dictionary 
attack is the fastest method - there's no limitation on password length. 
Known Plaintext attack instantly decrypts an archive if there is at least 
one file from the archive available unencrypted, regardless of the password 
length.

M.