RHSA-2010:0198 - Security Advisory

Topic

Updated openldap packages that fix one security issue and several bugs are
now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate
security impact. A Common Vulnerability Scoring System (CVSS) base score,
which gives a detailed severity rating, is available from the CVE link in
the References section.

Description

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

A flaw was found in the way OpenLDAP handled NUL characters in the
CommonName field of X.509 certificates. An attacker able to get a
carefully-crafted certificate signed by a trusted Certificate Authority
could trick applications using OpenLDAP libraries into accepting it by
mistake, allowing the attacker to perform a man-in-the-middle attack.
(CVE-2009-3767)

This update also fixes the following bugs:

• the ldap init script did not provide a way to alter system limits for the

slapd daemon. A variable is now available in "/etc/sysconfig/ldap" for this
option. (BZ#527313)

• applications that use the OpenLDAP libraries to contact a Microsoft

Active Directory server could crash when a large number of network
interfaces existed. This update implements locks in the OpenLDAP library
code to resolve this issue. (BZ#510522)

• when slapd was configured to allow client certificates, approximately 90%

of connections froze because of a large CA certificate file and slapd not
checking the success of the SSL handshake. (BZ#509230)

• the OpenLDAP server would freeze for unknown reasons under high load.

These packages add support for accepting incoming connections by new
threads, resolving the issue. (BZ#507276)

• the compat-openldap libraries did not list dependencies on other

libraries, causing programs that did not specifically specify the libraries
to fail. Detection of the Application Binary Interface (ABI) in use on
64-bit systems has been added with this update. (BZ#503734)

• the OpenLDAP libraries caused applications to crash due to an unprocessed

network timeout. A timeval of -1 is now passed when NULL is passed to LDAP.
(BZ#495701)

• slapd could crash on a server under heavy load when using rwm overlay,

caused by freeing non-allocated memory during operation cleanup.
(BZ#495628)

• the ldap init script made a temporary script in "/tmp/" and attempted to

execute it. Problems arose when "/tmp/" was mounted with the noexec option.
The temporary script is no longer created. (BZ#483356)

• the ldap init script always started slapd listening on ldap:/// even if

instructed to listen only on ldaps:///. By correcting the init script, a
user can now select which ports slapd should listen on. (BZ#481003)

• the slapd manual page did not mention the supported options -V and -o.

(BZ#468206)

• slapd.conf had a commented-out option to load the syncprov.la module.

Once un-commented, slapd crashed at start-up because the module had already
been statically linked to OpenLDAP. This update removes "moduleload
syncprov.la" from slapd.conf, which resolves this issue. (BZ#466937)

• the migrate_automount.pl script produced output that was unsupported by

autofs. This is corrected by updating the output LDIF format for automount
records. (BZ#460331)

• the ldap init script uses the TERM signal followed by the KILL signal

when shutting down slapd. Minimal delay between the two signals could cause
the LDAP database to become corrupted if it had not finished saving its
state. A delay between the signals has been added via the "STOP_DELAY"
option in "/etc/sysconfig/ldap". (BZ#452064)

• the migrate_passwd.pl migration script had a problem when number fields

contained only a zero. Such fields were considered to be empty, leading to
the attribute not being set in the LDIF output. The condition in
dump_shadow_attributes has been corrected to allow for the attributes to
contain only a zero. (BZ#113857)

• the migrate_base.pl migration script did not handle third level domains

correctly, creating a second level domain that could not be held by a
database with a three level base. This is now allowed by modifying the
migrate_base.pl script to generate only one domain. (BZ#104585)

Users of OpenLDAP 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.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 104585 - migrate_base.pl broken with dc=X,dc=Y,dc=Z configuration
• BZ - 113857 - migrate_passwd.pl problems with '0' fields
• BZ - 460331 - openldap-server's migrate_automount.pl produces obsolete output
• BZ - 466937 - moduleload syncprov.la not found
• BZ - 468206 - slapd and slapcat : man pages details
• BZ - 481003 - Wrong init script : slapd always starts with option "ldap:///"
• BZ - 483356 - /etc/init.d/ldap script assumes files in /tmp can be executed
• BZ - 495701 - LDAP queries fail entirely on a (temporarily) slow server
• BZ - 503734 - 64bit shared libs in compat-openldap do not link to other libs
• BZ - 509230 - ldaps fails if TLSVerifyClient=allow unless slapd is run with -d2
• BZ - 510522 - LDAP causes crashes when attempting to authenticate with Active Directory
• BZ - 530715 - CVE-2009-3767 OpenLDAP: Doesn't properly handle NULL character in subject Common Name
• BZ - 559520 - openldap cannot start when kerberos is enable, found by PES
• BZ - 562714 - openldap init script does not handle listen uris properly

CVEs

• CVE-2009-3767

References

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