RHSA-2005:767 - Security Advisory

Topic

Updated openldap and nss_ldap packages that correct a potential password
disclosure issue and possible authentication vulnerability are now available.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

Description

OpenLDAP is an open source suite of LDAP (Lightweight Directory Access
Protocol) applications and development tools.

The nss_ldap module is an extension for use with GNU libc which allows
applications to, without internal modification, consult a directory service
using LDAP to supplement information that would be read from local files
such as /etc/passwd, /etc/group, and /etc/shadow.

A bug was found in the way OpenLDAP, nss_ldap, and pam_ldap refer LDAP
servers. If a client connection is referred to a different server, it is
possible that the referred connection will not be encrypted even if the
client has "ssl start_tls" in its ldap.conf file. The Common
Vulnerabilities and Exposures project has assigned the name CAN-2005-2069
to this issue.

A bug was found in the way the pam_ldap module processed certain failure
messages. If the server includes supplemental data in an authentication
failure result message, but the data does not include any specific error
code, the pam_ldap module would proceed as if the authentication request
had succeeded, and authentication would succeed. The Common Vulnerabilities
and Exposures project has assigned the name CAN-2005-2641 to this issue.

Additionally the following issues are corrected in this erratum.

• The OpenLDAP upgrading documentation has been updated.
• Fix a database deadlock locking issue.
• A fix where slaptest segfaults on exit after successful check.
• The library libslapd_db-4.2.so is now located in an

architecture-dependent directory.

• The LDAP client no longer enters an infinite loop when the server returns

a reference to itself.

• The pam_ldap module adds the ability to check user passwords using a

directory server to PAM-aware applications.

• The directory server can now include supplemental information regarding

the state of the user's account if a client indicates that it supports
such a feature.

All users of OpenLDAP and nss_ldap are advised to upgrade to these updated
packages, which contain backported fixes that resolve these issues.

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/

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 - 159151 - Authconfig update creates a problem with OpenLDAP server
• BZ - 162482 - CAN-2005-2069 openldap password disclosure issue
• BZ - 166163 - CAN-2005-2641 pam_ldap policy vulnerability

CVEs

• CVE-2005-2069
• CVE-2005-2641

References

(none)