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COMMAND canna SYSTEMS AFFECTED Those using canna PROBLEM Following is based on Debian Security Advisory. The canna package as distributed in Debian GNU/Linux 2.1 can be remotely exploited to gain access. This could be done by overflowing a buffer by sending a SR_INIT command with a very long usernamd or groupname. The Canna server contains an overflowable buffer which may be exploited by a remote user to execute arbitrary code on the local system as user 'bin'. Remote users can run arbitrary code as user 'bin' on the local system. Depending on the local system configuration, the attacker may be able to upgrade privileges further by exploiting local vulnerabilities. If you have not chosen to install the Canna port/package, then your system is not vulnerable to this problem. Note that FreeBSD says about local and Debian about remote vulnerability. SOLUTION This has been fixed in version 3.5b2-24slink1, and recommend that you upgrade your canna package immediately (for Debian users). For FreeBSD: 1) Deinstall the Canna port/package, if you you have installed it. 2) Consider limiting remote access to the Canna server using ipfw(8) or ipf(8). 3) Create a /etc/hosts.canna file on the Canna server and list the hosts which you wish to allow access to the Canna server. For example, if you want to allow access via localhost only, include the following in your /etc/hosts.canna file: localhost unix If you want to allow access via localhost and some-other-host.com, which has IP address x.y.z.w, include the following: localhost unix x.y.z.w Solution is one of the following: 1) Upgrade your entire ports collection and rebuild the Canna port. 2) Deinstall the old package and install a new package dated after the correction date (2000-06-29), obtained from: ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/japanese/ja-Canna-3.2.2.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/japanese/ja-Canna-3.2.2.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/alpha/packages-4-stable/japanese/ja-Canna-3.2.2.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/japanese/ja-Canna-3.2.2.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/alpha/packages-5-current/japanese/ja-Canna-3.2.2.tgz 3) download a new port skeleton for the Canna port from: http://www.freebsd.org/ports/ and use it to rebuild the port.