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Date: Tue, 19 Oct 1999 23:06:07 -0400
From: Bill Nottingham <notting@redhat.com>
To: redhat-watch-list@redhat.com
Subject: [RHSA-1999:041-02] File access problems in lpr/lpd

---------------------------------------------------------------------
		   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 <filename>
 
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  <filename>
 
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 <filename>

Note that you need RPM >= 3.0 to check GnuPG keys.

10. References:



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