Bugtraq mailing list archives
Re: OpenSSH/PAM timing attack allows remote users identification
From: Marco Ivaldi <raptor () mediaservice net>
Date: Mon, 5 May 2003 14:55:51 +0200 (CEST)
On Thu, 1 May 2003, Ethan Benson wrote:
ive noticed something similar in its handling of PermitRootLogin, if this option is set to `no' you get the following behavior: $ ssh root@host root@host's password: <- arbitrary (non-null) string [2 secs delay] Permission denied, please try again.a $ ssh root@host root@host's password: <- correct root password [no delay] Permission denied, please try again. i haven't checked the current version to see if this is still true.
It is, also in the latest OpenSSH_3.6.1p2. I'm not sure if this behaviour has serios security implications, however it can be "fixed" applying the same workaround suggested for CAN-2003-0190: use the "nodelay" option for pam_unix.so. -- Marco Ivaldi Chief Security Officer Data Security Division @ Mediaservice.net Srl http://mediaservice.net/
Current thread:
- Re: OpenSSH/PAM timing attack allows remote users identification Ethan Benson (May 01)
- Re: OpenSSH/PAM timing attack allows remote users identification Nicolas Couture (May 02)
- Re: OpenSSH/PAM timing attack allows remote users identification Marco Ivaldi (May 05)
- <Possible follow-ups>
- Re: OpenSSH/PAM timing attack allows remote users identification Nicolas Couture (May 01)
- Re: OpenSSH/PAM timing attack allows remote users identification ilja van sprundel (May 02)
- Re: OpenSSH/PAM timing attack allows remote users identification Thilo Schulz (May 02)
- Re: OpenSSH/PAM timing attack allows remote users identification Marco Ivaldi (May 02)
- Re: OpenSSH/PAM timing attack allows remote users identification Michael Shigorin (May 02)
- Re: OpenSSH/PAM timing attack allows remote users identification Marco Ivaldi (May 02)
- Re: OpenSSH/PAM timing attack allows remote users identification Karl-Heinz Haag (May 02)