Date: Tue, 19 Oct 1999 23:06:07 -0400
From: Bill Nottingham notting@redhat.com
To: redhat-watch-list@redhat.com
Reply to: redhat-watch-list@redhat.com
Red Hat, Inc. Security Advisory
Synopsis: File access problems in lpr/lpd
Advisory ID: RHSA-1999:041-02
Issue date: 1999-10-17
Updated on: 1999-10-19
Keywords: lpr lpd permissions
Cross references:
Revision History:
1999-10-19: New packages, to fix a remote printing bug. Add note
about local printing fix for Red Hat Linux 6.1.
1. Topic:
There are potential problems with file access checking in the
lpr and lpd programs. These could allow users to potentially print
files they do not have access to. Also, there are bugs in remote
printing in the lpd that shipped with Red Hat Linux 6.1.
2. Bug IDs fixed (http://developer.redhat.com/bugzilla
for more info):
5122 5540 5697 5832 5835 5903 5949
3. Relevant releases/architectures:
Red Hat Linux 4.x, all architectures
Red Hat Linux 5.x, all architectures
Red Hat Linux 6.x, all architectures
4. Obsoleted by:
5. Conflicts with:
6. RPMs required:
Red Hat Linux 4.x:
Intel:
ftp://updates.redhat.com/4.2/i386/lpr-0.44-0.4.2.i386.rpm
Alpha:
ftp://updates.redhat.com/4.2/alpha/lpr-0.44-0.4.2.alpha.rpm
Sparc:
ftp://updates.redhat.com/4.2/sparc/lpr-0.44-0.4.2.sparc.rpm
Source packages:
ftp://updates.redhat.com/4.2/SRPMS/lpr-0.44-0.4.2.src.rpm
Red Hat Linux 5.x:
Intel:
ftp://updates.redhat.com/5.2/i386/lpr-0.44-0.5.2.i386.rpm
Alpha:
ftp://updates.redhat.com/5.2/alpha/lpr-0.44-0.5.2.alpha.rpm
Sparc:
ftp://updates.redhat.com/5.2/sparc/lpr-0.44-0.5.2.sparc.rpm
Source packages:
ftp://updates.redhat.com/5.2/SRPMS/lpr-0.44-0.5.2.src.rpm
Red Hat Linux 6.x:
Intel:
ftp://updates.redhat.com/6.1/i386/lpr-0.44-1.i386.rpm
Alpha:
ftp://updates.redhat.com/6.0/alpha/lpr-0.44-1.alpha.rpm
Sparc:
ftp://updates.redhat.com/6.0/sparc/lpr-0.44-1.sparc.rpm
Source packages:
ftp://updates.redhat.com/6.1/SRPMS/lpr-0.44-1.src.rpm
7. Problem description:
There are two problems in the lpr and lpd programs. By
exploiting a race between the access check and the actual file
opening, it is potentially possible to have lpr read a file as root
that the user does not have access to. Also, the lpd program would
blindly open queue files as root; by use of the ‘-s’ flag to lpr,
it was possible to have lpd print files that the user could not
access.
Thanks go to Tymm Twillman for pointing out these
vulnerabilities.
Also, various bugs in remote printing that were present in the
lpd released with Red Hat Linux 6.1 have been fixed.
(1999-10-19)
Another problem with remote printing was fixed in lpr-0.44. If you
are experiencing problems with remote printing in the previous
errata update, it is recommended that you upgrade. There are no
known security issues with the previous errata packages.
If you are experiencing problems with local printing in Red Hat
Linux 6.1, make sure that you have:
alias parport_lowlevel parport_pc
in your /etc/conf.modules file.
8. Solution:
For each RPM for your particular architecture, run:
rpm -Uvh
where filename is the name of the RPM.
9. Verification:
MD5 sum Package Name
d2f5c64c365e2c0d817f76afa8060b2e lpr-0.44-0.4.2.i386.rpm 7ae7d15c22c8d0d939c4ced691264bbd lpr-0.44-0.4.2.alpha.rpm 19fcc1359c8b809f452f69db735120ae lpr-0.44-0.4.2.sparc.rpm 1522e6d70af352db4dabeb2515c1393b lpr-0.44-0.4.2.src.rpm 5b3c41813873a243971d3d96df54b911 lpr-0.44-0.5.2.i386.rpm 0985ea8badbda09fcb001f9b5ec82585 lpr-0.44-0.5.2.alpha.rpm b14b9eee10687d313d352dbd1854ba6d lpr-0.44-0.5.2.sparc.rpm 0852577b4e147c72658d474face2046e lpr-0.44-0.5.2.src.rpm 43fe30820e3a2769cf874f1d858f0b48 lpr-0.44-1.i386.rpm 995dd83e73ea4bb711e1a27b640bc347 lpr-0.44-1.alpha.rpm b75b18290d87d4f04d14f5db7f94389c lpr-0.44-1.sparc.rpm 65db0fbdb1661498835e1e0de945336a lpr-0.44-1.src.rpm
These packages are signed with GnuPG by Red Hat Inc. for
security. Our key is available at:
http://www.redhat.com/corp/contact.html
You can verify each package with the following command:
rpm –checksig
If you only wish to verify that each package has not been
corrupted or tampered with, examine only the md5sum with the
following command:
rpm –checksig –nogpg
Note that you need RPM >= 3.0 to check GnuPG keys.
10. References: