Public bug reported: After upgrading from Ubuntu 18.04 to 20.04 a lot of authentification problems appeared on our mail cluster (Postfix/Dovecot).
I found out it was due to the format of the salt in the hashed passphrase. All non working hashes have a '&' character in the salt: 1$abcd&$F3E5DEjSFJpzgeU.Wzu/W.\ This salt format worked on Ubuntu 16.04 and 18.04: perl -E 'say crypt($ARGV[0], $ARGV[1])' 'test' '$1$abcd&$F3E5DEjSFJpzgeU.Wzu/W.\' $1$abcd&$F3E5DEjSFJpzgeU.Wzu/W. But not on Ubuntu 20.04: perl -E 'say crypt($ARGV[0], $ARGV[1])' 'test' '$1$abcd&$F3E5DEjSFJpzgeU.Wzu/W.\' *0 The upstream already fixed this problem in libxcrypt 4.4.17: "Salt string compatibility with generic implementations (issue #105)." https://github.com/besser82/libxcrypt/blob/develop/NEWS and here the link to the github issue and commit: https://github.com/besser82/libxcrypt/issues/105 https://github.com/besser82/libxcrypt/commit/f05159c73a7415da1a8430ee2db6ec8035b5d2e8 It would be really nice if you could upgrade the version of libxcrypt to 4.4.17 for focal. A package for Hirsute Hippo with 4.4.17 already exists and i installed it on one of our focal mail nodes which solved the problem, but i'm not sure if i should use libcrypt1 and libcrypt-dev dpkg from 21.04 developement version. Thanks for your help, Alex ** Affects: libxcrypt (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1915904 Title: Salt string compatibility problem 4.4.10 focal To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libxcrypt/+bug/1915904/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
