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COMMAND tnef SYSTEMS AFFECTED tnef < 0-124 PROBLEM Tnef extracts eMails compressed with MS-Outlook. The compressed file includes the path name to which the decompressed data should be written. By specifing a path name like /etc/passwd and sending a compressed mail to root an adversary could gain remote root access to a system by overwriting the local password database. The same could happen if a mail virus scanner, like AMaVIS, process' a malicious mail. TNEF support was added to AMaViS 0.2.0-pre6-clm-rl-8-20000604 (previous versions are therefore *not* affected), but AMaViS does not run as root when used with qmail, exim and postfix. AMaViS is run as root, when used with sendmail and AMaViS is called via Mlocal. AMaViS may not run as root, when used with sendmail and the new relay scanning setup for AMaViS (--enable-relay). SOLUTION It's also possible to use the '-x' option of tnef to specify the outputfile. For SuSE Linux: ftp://ftp.suse.com/pub/suse/axp/update/6.3/ap1/tnef-0-124.alpha.rpm ftp://ftp.suse.com/pub/suse/axp/update/6.3/zq1/tnef-0-124.src.rpm ftp://ftp.suse.com/pub/suse/axp/update/6.4/ap1/tnef-0-124.alpha.rpm ftp://ftp.suse.com/pub/suse/axp/update/6.4/zq1/tnef-0-124.src.rpm ftp://ftp.suse.com/pub/suse/i386/update/6.3/ap1/tnef-0-124.i386.rpm ftp://ftp.suse.com/pub/suse/i386/update/6.3/zq1/tnef-0-124.src.rpm ftp://ftp.suse.com/pub/suse/i386/update/6.4/ap1/tnef-0-124.i386.rpm ftp://ftp.suse.com/pub/suse/i386/update/6.4/zq1/tnef-0-124.src.rpm ftp://ftp.suse.com/pub/suse/ppc/update/6.3/ap1/tnef-0-124.ppc.rpm ftp://ftp.suse.com/pub/suse/ppc/update/6.3/zq1/tnef-0-124.src.rpm ftp://ftp.suse.com/pub/suse/ppc/update/6.4/ap1/tnef-0-124.ppc.rpm ftp://ftp.suse.com/pub/suse/ppc/update/6.4/zq1/tnef-0-124.src.rpm A fix for this possible security hole was provided in AMaViS 0.2.0-pre6-clm-rl-8-20000704. It's available at http://sourceforge.net/projects/amavis http://cvsweb.amavis.org/ http://www.computer-networking.de/~link/security/amavis-patch.php3#latest_sources It is recommended to use Mark Simpson's TNEF which does not suffer from this security problem, as it supportes the -d flag to extract files to a specific directory.