Red Hat Security Advisory

Synopsis:          Updated pam packages
Advisory ID:       RHSA-2004:304-01
Issue date:        2004-08-18
Updated on:        2004-08-18
Product:           Red Hat Enterprise Linux
Keywords:          pam pam_wheel pam_lastlog
CVE Names:         CAN-2003-0388
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1. Summary:

Updated pam packages that fix a security vulnerability are now available
for Red Hat Enterprise Linux 2.1.

2. Relevant releases/architectures:

Red Hat Enterprise Linux AS (Advanced Server) version 2.1 - i386, ia64
Red Hat Linux Advanced Workstation 2.1 - ia64
Red Hat Enterprise Linux ES version 2.1 - i386
Red Hat Enterprise Linux WS version 2.1 - i386

3. Problem description:

PAM (Pluggable Authentication Modules) is a system security tool that
allows system administrators to set an authentication policy without
having to recompile programs that handle authentication.

These updates fix a potential security problem present in the
pam_wheel module.  These updates correct a bug in the pam_lastlog
module which prevented it from properly manipulating the /var/log/lastlog
entry for users with very high user IDs.

The pam_wheel module is used to restrict access to a particular service
based on group membership.  If the pam_wheel module was used with the
"trust" option enabled, but without the "use_uid" option, any local
user would be able to spoof the username returned by getlogin(). The user
could therefore gain access to a superuser account without supplying a
password.  In Red Hat Enterprise Linux 2.1, pam_wheel is not used by
default.  The Common Vulnerabilities and Exposures project (cve.mitre.org)
has assigned the name CAN-2003-0388 to this issue.

When manipulating the entry in /var/log/lastlog, which corresponds to a
given user, the pam_lastlog module calculates the location of the entry by
multiplying the UID and the length of an entry in the file.  On some
systems, the result of this calculation would mistakenly be truncated to 32
bits for users with sufficiently high UIDs.

All users of pam should upgrade to these updated packages, which
resolve these issues.

4. Solution:

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.  Use Red Hat
Network to download and update your packages.  To launch the Red Hat
Update Agent, use the following command:

    up2date

For information on how to install packages manually, refer to the
following Web page for the System Administration or Customization
guide specific to your system:

     http://www.redhat.com/docs/manuals/enterprise/


5. Bug IDs fixed  (http://bugzilla.redhat.com/ for more info):

98826 - CAN-2003-0388 pam_wheel uses getlogin in insecure fashion

6. RPMs required:

Red Hat Enterprise Linux AS (Advanced Server) version 2.1:

SRPMS: 

5c78062a595e3443d22ca145b774cd34  pam-0.75-46.9.src.rpm

i386:
1a72acefcb8b2c7bfb875f9024ae818b  pam-0.75-46.9.i386.rpm
e129fb8519d309ab26d3045bd91bb2e3  pam-devel-0.75-46.9.i386.rpm

ia64:
851a5e5a7f78b4a4cbde060c62ab1e7d  pam-0.75-46.9.ia64.rpm
3b23b14f7cfbcf2a73d21fd3a0b18bda  pam-devel-0.75-46.9.ia64.rpm

Red Hat Linux Advanced Workstation 2.1:

SRPMS: 

5c78062a595e3443d22ca145b774cd34  pam-0.75-46.9.src.rpm

ia64:
851a5e5a7f78b4a4cbde060c62ab1e7d  pam-0.75-46.9.ia64.rpm
3b23b14f7cfbcf2a73d21fd3a0b18bda  pam-devel-0.75-46.9.ia64.rpm

Red Hat Enterprise Linux ES version 2.1:

SRPMS: 

5c78062a595e3443d22ca145b774cd34  pam-0.75-46.9.src.rpm

i386:
1a72acefcb8b2c7bfb875f9024ae818b  pam-0.75-46.9.i386.rpm
e129fb8519d309ab26d3045bd91bb2e3  pam-devel-0.75-46.9.i386.rpm

Red Hat Enterprise Linux WS version 2.1:

SRPMS: 

5c78062a595e3443d22ca145b774cd34  pam-0.75-46.9.src.rpm

i386:
1a72acefcb8b2c7bfb875f9024ae818b  pam-0.75-46.9.i386.rpm
e129fb8519d309ab26d3045bd91bb2e3  pam-devel-0.75-46.9.i386.rpm

These packages are GPG signed by Red Hat for security.  Our key and 
details on how to verify the signature are available from
 

7. References:
 
CVE -CVE-2003-0388

8. Contact:

The Red Hat security contact is <secalert@redhat.com>.  More contact
details at  

Copyright 2004 Red Hat, Inc.