util-linux umount privilege escalation

ID SSA-2005-0913005002
Type slackware
Reporter Slackware Linux Project
Modified 2005-09-13T00:50:02


New util-linux packages are available for Slackware 8.1, 9.0, 9.1, 10.0, 10.1, and -current to fix a security issue with umount. A bug in the '-r' option could allow flags in /etc/fstab to be improperly dropped on user-mountable volumes, allowing a user to gain root privileges.

For more details, see David Watson's post to BugTraq:


Here are the details from the Slackware 10.1 ChangeLog:

patches/packages/util-linux-2.12p-i486-2.tgz: Patched an issue with umount where if the umount failed when the '-r' option was used, the filesystem would be remounted read-only but without any extra flags specified in /etc/fstab. This could allow an ordinary user able to mount a floppy or CD (but with nosuid, noexec, nodev, etc in /etc/fstab) to run a setuid binary from removable media and gain root privileges. Reported to BugTraq by David Watson: http://www.securityfocus.com/archive/1/410333 ( Security fix )

Where to find the new packages:

Updated package for Slackware 8.1: ftp://ftp.slackware.com/pub/slackware/slackware-8.1/patches/packages/util-linux-2.11r-i386-3.tgz

Updated package for Slackware 9.0: ftp://ftp.slackware.com/pub/slackware/slackware-9.0/patches/packages/util-linux-2.11z-i386-2.tgz

Updated package for Slackware 9.1: ftp://ftp.slackware.com/pub/slackware/slackware-9.1/patches/packages/util-linux-2.12-i486-2.tgz

Updated package for Slackware 10.0: ftp://ftp.slackware.com/pub/slackware/slackware-10.0/patches/packages/util-linux-2.12a-i486-2.tgz

Updated package for Slackware 10.1: ftp://ftp.slackware.com/pub/slackware/slackware-10.1/patches/packages/util-linux-2.12p-i486-2.tgz

Updated package for Slackware -current: ftp://ftp.slackware.com/pub/slackware/slackware-current/slackware/a/util-linux-2.12p-i486-2.tgz

MD5 signatures:

Slackware 8.1 package: 3b3025faf0a40428f2861fa2967c13d3 util-linux-2.11r-i386-3.tgz

Slackware 9.0 package: 41b08961548899ca10fa93d16a7ab516 util-linux-2.11z-i386-2.tgz

Slackware 9.1 package: 4890b834bac6d7490c1daf5bc7bbff55 util-linux-2.12-i486-2.tgz

Slackware 10.0 package: 3e628cf4d6db843a1dd63e2fa7f3aba1 util-linux-2.12a-i486-2.tgz

Slackware 10.1 package: 01722ab0146969c6cde9f99698864606 util-linux-2.12p-i486-2.tgz

Slackware -current package: 21e318a9f04dc6588916945713312bf3 util-linux-2.12p-i486-2.tgz

Installation instructions:

Upgrade the package as root: > upgradepkg util-linux-2.12p-i486-2.tgz