-----BEGIN PGP SIGNED MESSAGE----- ============================================================================= FreeBSD-SA-02:06 Security Advisory FreeBSD, Inc. Topic: sudo port may enable local privilege escalation Category: ports Module: sudo Announced: 2002-01-16 Credits: Sebastian Krahmer Affects: Ports collection prior to the correction date Corrected: 2002-01-15 02:56:33 UTC FreeBSD only: NO I. Background Sudo is a program designed to allow a sysadmin to give limited root privileges to users and log root activity. II. Problem Description The sudo port, versions prior to sudo-1.6.4.1, contains a vulnerability that may allow a local user to obtain superuser privileges. If a user who has not been authorized by the system administrator (listed in the `sudoers' file) attempts to use sudo, sudo will send an email alert. When it does so, it invokes the system mailer with superuser privileges, and with most of the user's environment intact. The sudo 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 6000 third-party applications in a ready-to-install format. The ports collection shipped with FreeBSD 4.4 contains this problem since it was discovered after 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 If the system mailer's behavior can be influenced by the settings of environmental variables, then an attacker may obtain superuser privileges. There is at least one mailer (postfix) that can be influenced in this fashion. IV. Workaround 1) Deinstall the sudo port/package if you have it installed. V. Solution 1) Upgrade your entire ports collection and rebuild the 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/security/sudo-1.6.4.1.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/security/sudo-1.6.4.1.tgz [alpha] Packages are not automatically generated for the alpha architecture at this time due to lack of build resources. NOTE: It may be several days before updated packages are available. 3) Download a new port skeleton for the sudo 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 VI. Correction details The following list contains the revision numbers of each file that was corrected in the FreeBSD ports collection. Path Revision - ------------------------------------------------------------------------- ports/security/sudo/Makefile 1.43 ports/security/sudo/distinfo 1.26 - ------------------------------------------------------------------------- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (FreeBSD) Comment: For info see http://www.gnupg.org iQCVAwUBPEYIq1UuHi5z0oilAQEgTAP/YXD+lSngGwbloUn09xvwgn8i5uGaEX5O Rj1v7XM3HRT/Gmr1CJiK7LtMbj/iilHzC2YiTAUHyxYzdEU7k9SnLgxK6rcSYNql 5wkYL1asHQhFPYejEqQVPKejrr4L/+/bYmQbkLKc9EMdErnhYoNrw6QbN+XvmO6p oAzSK07ixi4= =rmb8 -----END PGP SIGNATURE-----