-----BEGIN PGP SIGNED MESSAGE----- ============================================================================= FreeBSD-SA-01:36 Security Advisory FreeBSD, Inc. Topic: samba ports contain locally exploitable /tmp races Category: ports Module: samba Announced: 2001-04-23 Credits: Marcus Meissner Affects: Ports collection prior to the correction date. Corrected: 2001-04-18 Vendor status: Updated version released FreeBSD only: No I. Background Samba is an implementation of the Server Message Block (SMB) protocol. II. Problem Description The samba ports, versions prior to samba-2.0.8 and samba-devel-2.2.0, contain /tmp races that may allow local users to cause arbitrary files and devices to be overwritten. Due to easily predictable printer queue cache file names, local users may create symbolic links to any file or device causing it to be corrupted when a remote user accesses a printer. In addition, the file will be left with world- writable permission allowing any user to enter their own data. The samba ports are not installed by default, nor are they "part of FreeBSD" as such: they are part of the FreeBSD ports collection, which contains over 5000 third-party applications in a ready-to-install format. The ports collections shipped with FreeBSD 3.5.1 and 4.2 contain this problem since it was discovered after the releases. The ports collection that shipped with FreeBSD 4.3 is not vulnerable since this problem was corrected prior to the 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 Unprivileged local users may cause arbitrary files or devices to be corrupted and gain increased privileges on the local system. If you have not chosen to install the samba ports/packages, then your system is not vulnerable to this problem. Samba servers that do not have any printers configured are not vulnerable. IV. Workaround Deinstall the samba port/package, if you have installed it. V. Solution One of the following: 1) Upgrade your entire ports collection and rebuild the samba port. 2) Deinstall the old package and install a new package dated after the correction date, obtained from: [i386] ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/net/samba-2.0.8.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/net/samba-2.0.8.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/net/samba-devel-2.2.0.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/net/samba-devel-2.2.0.tgz NOTE: it may be several days before updated packages are available. [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 samba 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-3-stable/devel/portcheckout-2.0.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/devel/portcheckout-2.0.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/alpha/packages-4-stable/devel/portcheckout-2.0.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/devel/portcheckout-2.0.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/alpha/packages-5-current/devel/portcheckout-2.0.tgz -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (FreeBSD) Comment: FreeBSD: The Power To Serve iQCVAwUBOuTqtVUuHi5z0oilAQEaFAQAlriJxzRK8s/UnIJliIIGqZgdp+bTiKfs XV66+DD0+RZtWcsjPx5imCCfsWJgdurq9JpM6iWYJCir34wargJygpZRWSU/Pnov yKw2IrNbOVkp4ASRbXCqLm+Z6WZKXhbJN+f/8N+ts2XVk+QJrZWzCRqa1ynyx1I1 MpvXhM9lTvk= =qspP -----END PGP SIGNATURE-----