RHSA-2006:0719 - Security Advisory

Topic

Updated nss_ldap packages that fix a security flaw are now available for
Red Hat Enterprise Linux 4.

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

Description

nss_ldap is a set of C library extensions that allow X.500 and LDAP
directory servers to be used as primary sources for aliases, ethers,
groups, hosts, networks, protocols, users, RPCs, services, and shadow
passwords.

A flaw was found in the way nss_ldap handled a PasswordPolicyResponse
control sent by an LDAP server. If an LDAP server responded to an
authentication request with a PasswordPolicyResponse control, it was
possible for an application using nss_ldap to improperly authenticate
certain users. (CVE-2006-5170)

This flaw was only exploitable within applications which did not properly
process nss_ldap error messages. Only xscreensaver is currently known to
exhibit this behavior.

All users of nss_ldap should upgrade to these updated packages, which
contain a backported patch that resolves this issue.

Solution

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

This update is available via Red Hat Network. 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.

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 - 207286 - CVE-2006-5170 When using LDAP for authentication, xscreensaver allows access if account locked out.

CVEs

• CVE-2006-5170

References

• http://www.redhat.com/security/updates/classification/#moderate