-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ________________________________________________________________________ OpenPKG Security Advisory The OpenPKG Project http://www.openpkg.org/security.html http://www.openpkg.org openpkg-security@openpkg.org openpkg@openpkg.org OpenPKG-SA-2003.035 06-Aug-2003 ________________________________________________________________________ Package: openssh Vulnerability: information leakage OpenPKG Specific: no Affected Releases: Affected Packages: Corrected Packages: OpenPKG CURRENT <= openssh-3.6.1p1-20030423 >= openssh-3.6.1p2-20030429 OpenPKG 1.3 none N.A. OpenPKG 1.2 <= openssh-3.5p1-1.2.1 >= openssh-3.5p1-1.2.2 Dependent Packages: none Description: According to a Mediaservice.net security advisory [0], an information leakage exists in OpenSSH [1] 3.6.1p1 and earlier if PAM support is enabled. When a user does not exists, an error message is sent immediately (without any delays) which allows remote attackers to determine valid usernames via a timing attack. OpenPKG installations are only affected if the package was build with option "with_pam" set to "yes" -- which is not the default. The Common Vulnerabilities and Exposures (CVE) project assigned the id CAN-2003-0190 [2] to the problem. We could only reproduce the problem on Linux. FreeBSD and Solaris are not vulnerable, the patch does not affect their behaviour. However, the problem is related to the PAM configuration, not the operating system. Using a non-default configuration might leak information on other operating systems, too. On Linux systems, a valid workaround is to add a "nodelay" option to the pam_unix.so auth. Please check whether you are affected by running "<prefix>/bin/rpm -q openssh". If you have the "openssh" package installed and its version is affected (see above), we recommend that you immediately upgrade it (see Solution). Solution: Select the updated source RPM appropriate for your OpenPKG release [5], fetch it from the OpenPKG FTP service [6] or a mirror location, verify its integrity [7], build a corresponding binary RPM from it [3] and update your OpenPKG installation by applying the binary RPM [4]. For the current release OpenPKG 1.2, perform the following operations to permanently fix the security problem (for other releases adjust accordingly). $ ftp ftp.openpkg.org ftp> bin ftp> cd release/1.2/UPD ftp> get openssh-3.5p1-1.2.2.src.rpm ftp> bye $ <prefix>/bin/rpm -v --checksig openssh-3.5p1-1.2.2.src.rpm $ <prefix>/bin/rpm --rebuild openssh-3.5p1-1.2.2.src.rpm $ su - # <prefix>/bin/rpm -Fvh <prefix>/RPM/PKG/openssh-3.5p1-1.2.2.*.rpm ________________________________________________________________________ References: [0] http://lab.mediaservice.net/advisory/2003-01-openssh.txt [1] http://www.openssh.com/ [2] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0190 [3] http://www.openpkg.org/tutorial.html#regular-source [4] http://www.openpkg.org/tutorial.html#regular-binary [5] ftp://ftp.openpkg.org/release/1.2/UPD/openssh-3.5p1-1.2.2.src.rpm [6] ftp://ftp.openpkg.org/release/1.2/UPD/ [7] http://www.openpkg.org/security.html#signature ________________________________________________________________________ For security reasons, this advisory was digitally signed with the OpenPGP public key "OpenPKG <openpkg@openpkg.org>" (ID 63C4CB9F) of the OpenPKG project which you can retrieve from http://pgp.openpkg.org and hkp://pgp.openpkg.org. Follow the instructions on http://pgp.openpkg.org/ for details on how to verify the integrity of this advisory. ________________________________________________________________________ -----BEGIN PGP SIGNATURE----- Comment: OpenPKG <openpkg@openpkg.org> iD8DBQE/MQR9gHWT4GPEy58RAiKkAKCpACytbxQN0ERLBbqNfmbZYYc59wCg6V33 XFH1dFEVD0jBbdBvvdIdIZM= =GtfK -----END PGP SIGNATURE-----