-----BEGIN PGP SIGNED MESSAGE----- ============================================================================= FreeBSD-SA-01:43 Security Advisory FreeBSD, Inc. Topic: fetchmail contains potentially exploitable buffer overflow Category: ports Module: fetchmail Announced: 2001-07-10 Credits: Wolfram Kleff Affects: Ports collection prior to the correction date. Corrected: 2001-06-15 Vendor status: Updated version released FreeBSD only: NO I. Background fetchmail is a program used to retrieve email from POP and IMAP servers. II. Problem Description The fetchmail port, versions prior to fetchmail-5.8.6, contains a potentially exploitable buffer overflow when rewriting headers longer than 512 bytes. This problem may allow remote users to cause fetchmail to crash and potentially execute arbitrary code as the user running fetchmail. The fetchmail port is not installed by default, nor is it "part of FreeBSD" as such: it is part of the FreeBSD ports collection, which contains over 5400 third-party applications in a ready-to-install format. The ports collection shipped with FreeBSD 4.3 is vulnerable to this problem since it was discovered after its release. FreeBSD makes no claim about the security of these third-party applications, although an effort is underway to provide a security audit of the most security-critical ports. III. Impact Remote users using specially crafted email messages may be able to cause fetchmail to crash and potentially execute arbitrary code as the user running fetchmail. If you have not chosen to install the fetchmail port/package, then your system is not vulnerable to this problem. IV. Workaround Deinstall the fetchmail port/package if you have installed it. V. Solution One of the following: 1) Upgrade your entire ports collection and rebuild the fetchmail port. 2) Deinstall the old package and install a new package dated after the correction date, obtained from the following directories: [i386] ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/mail/fetchmail-5.8.6.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/mail/fetchmail-5.8.6.tgz [alpha] Packages are not automatically generated for the alpha architecture at this time due to lack of build resources. 3) download a new port skeleton for the fetchmail port from: http://www.freebsd.org/ports/ and use it to rebuild the port. 4) Use the portcheckout utility to automate option (3) above. The portcheckout port is available in /usr/ports/devel/portcheckout or the package can be obtained from: ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/devel/portcheckout-2.0.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/devel/portcheckout-2.0.tgz -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (FreeBSD) Comment: FreeBSD: The Power To Serve iQCVAwUBO0sNt1UuHi5z0oilAQH3NAP/aozGB400MgGyT/mndBk39Y1tD1aPR1AN yDUG+ddeiskXWjR2UNUd3hqQNJ/8LNMqty8MYOVDB+4S+Pvk4MS2iXcW/4r8yPuT 2V0FfHos3ytxk/mujf7IlVhwp3fnGCFJpFJatgbhUUoU8gakl8BfR87zT77RbiDQ OuGG+fpBKEw= =zCcz -----END PGP SIGNATURE-----