possible remote root compromise in ssh

SuSE distributions contain the ssh package in the version 1.2.27. No later version is provided because of licensing issues. SuSE maintains the 1.2.27 version in a patched package. Three new patches have been added that workaround three independent security problems in the ssh package: a) SSHD-1 Logging Vulnerability (discovered and published by Jose Nazario, Crimelabs). Attackers can remotely brute-force passwords without getting noticed or logged. In the ssh package from the SuSE distribution, root login is allowed, as well as password authentication. Even though brute-forcing a password may take an enormous amount of time and resources, the issue is to be taken seriously. b) SSH1 session key recovery vulnerability (by (Ariel Waissbein, Agustin Azubel) - CORE SDI, Argentina, and David Bleichenbacher). Captured encrypted ssh traffic can be decrypted with some effort by obtaining the session key for the ssh session. The added patch in our package causes the ssh daemon to generate a new server key pair upon failure of an RSA operation (please note that the patch supplied with Iván Arce on bugtraq on Wed, 7 Feb 2001 has been corrected later on!). c) In 1998, the ssh-1 protocol was found to be vulnerable to an attack where arbitrary sequences could be inserted into the ssh-1 protocol layer. The attack was called “crc32 compensation attack”, and a fix was introduced (crc compensation attack detector in the ssh -v output) into the later versions of ssh. Michal Zalewski discovered that the fix in its most widely used implementation is defective. An integer overflow allows an attacker to overwrite arbitrary memory in the sshd process’ address space, which potentionally results in a remote root compromise. There are easy resorts that can be offered: a) switch to openssh (please use the openssh packages on ftp.suse.com from the same update directories as the ssh package update URLs below indicate). openssh is a different implementation of the ssh protocol that is compatible to the protocol versions 1 and 2. Openssh Version 2.3.0 does not suffer from the problems listed above. Versions before 2.3.0 are vulnerable to other problems, so please use the updates from the update directory on the ftp.suse.de ftp server. See section 2) of this announcement for the md5sums of the packages. b) upgrade your ssh package from the locations described below.