RHBA-2007:0300 - Bug Fix Advisory

Topic

Updated pam packages that resolve bugs in PAM modules are now available.

Description

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

The pam_unix module provides authentication based on system /etc/passwd and
/etc/shadow files or NIS. The module did not allow usernames beginning with
'.' or '_' characters which are allowed by useradd. The module also allowed
authentication based on truncated MD5 password in the system files which
would allow to authenticate with passwords different from the actual user's
password.

The pam_access module provides configurable authorization of user logins
based on their user name and remote machine from which they are logging in.
The updated packages add support for defining custom list separator used in
the configuration file of the module.

The pam_succeed_if module provides support for simple conditions in PAM
config file. The updated packages add support for service and list based
match in conditions.

The updated packages also add a new module pam_keyinit which can be used
for user keyring initialization in kernel.

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

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

To update all RPMs for your particular architecture, run:

rpm -Fvh [filenames]

where [filenames] is a list of the RPMs you wish to upgrade. Only those
RPMs which are currently installed will be updated. Those RPMs which are
not installed but included in the list will not be updated. Note that you
can also use wildcards (*.rpm) if your current directory *only* contains the
desired RPMs.

Please note that this update is also available via Red Hat Network. Many
people find this an easier way to apply updates. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:

up2date

This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.

If up2date fails to connect to Red Hat Network due to SSL
Certificate Errors, you need to install a version of the
up2date client with an updated certificate. The latest version of
up2date is available from the Red Hat FTP site and may also be
downloaded directly from the RHN website:

https://rhn.redhat.com/help/latest-up2date.pxt

Affected Products

• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for Power, big endian 4 ppc

Fixes

• BZ - 173926 - Support list and service match in pam_succeed_if
• BZ - 183218 - Add session keyring initialisation PAM module
• BZ - 201008 - Request for administrator-defined list separator parameter for pam_access.so
• BZ - 212136 - Mismatch of allowed usernames between useradd and pam_unix
• BZ - 219187 - A truncated md5 password in /etc/shadow is still valid.

CVEs

(none)

References

(none)