Using
7z l -slt archiveName.zip | less
I found that zip
on Ubuntu uses
Method = ZipCrypto Deflate
for encryption. I don't pretend to posses any knowledge about which algorithms are considered theoretically secure at the time of writing, though as per this googled paper (cited here too) and the references therein, ZipCrypto
is broken, while ZipCrypto Deflate
isn't much better.
As suggested here, 7za
does use AES
(probably AES256
) which is the de facto symmetric encryption cipher at the time of writing. I therefore suggest using it over zip
.
Please remember that "I want to use highly secure encryption" does not guarantee that your files can't be read by someone else. Information security is a complex topic and cryptographically secure algorithms alone do not guarantee it. A humorous elaboration of this may be found here.