RHSA-2016:2765 - Security Advisory

Topic

An update for 389-ds-base is now available for Red Hat Enterprise Linux 6.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

389 Directory Server is an LDAP version 3 (LDAPv3) compliant server. The base packages include the Lightweight Directory Access Protocol (LDAP) server and command-line utilities for server administration.

Security Fix(es):

• It was found that 389 Directory Server was vulnerable to a flaw in which the default ACI (Access Control Instructions) could be read by an anonymous user. This could lead to leakage of sensitive information. (CVE-2016-5416)
• An information disclosure flaw was found in 389 Directory Server. A user with no access to objects in certain LDAP sub-tree could send LDAP ADD operations with a specific object name. The error message returned to the user was different based on whether the target object existed or not. (CVE-2016-4992)
• It was found that 389 Directory Server was vulnerable to a remote password disclosure via timing attack. A remote attacker could possibly use this flaw to retrieve directory server password after many tries. (CVE-2016-5405)

The CVE-2016-5416 issue was discovered by Viktor Ashirov (Red Hat); the CVE-2016-4992 issue was discovered by Petr Spacek (Red Hat) and Martin Basti (Red Hat); and the CVE-2016-5405 issue was discovered by William Brown (Red Hat).

Bug Fix(es):

• Previously, a bug in the changelog iterator buffer caused it to point to an incorrect position when reloading the buffer. This caused replication to skip parts of the changelog, and consequently some changes were not replicated. This bug has been fixed, and replication data loss due to an incorrectly reloaded changelog buffer no longer occurs. (BZ#1354331)
• Previously, if internal modifications were generated on a consumer (for example by the Account Policy plug-in) and additional changes to the same attributes were received from replication, a bug caused Directory Server to accumulate state information on the consumer. The bug has been fixed by making sure that replace operations are only applied if they are newer than existing attribute deletion change sequence numbers (CSNs), and state information no longer accumulates in this situation. (BZ#1379599)

Enhancement(s):

• In a multi-master replication environment where multiple masters receive updates at the same time, it was previously possible for a single master to obtain exclusive access to a replica and hold it for a very long time due to problems such as a slow network connection. During this time, other masters were blocked from accessing the same replica, which considerably slowed down the replication process. This update adds a new configuration attribute, "nsds5ReplicaReleaseTimeout", which can be used to specify a timeout in seconds. After the specified timeout period passes, the master releases the replica, allowing other masters to access it and send their updates. (BZ#1358390)

Solution

For details on how to apply this update, which includes the changes
described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, the 389 server service will be restarted
automatically.

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386

Fixes

• BZ - 1347760 - CVE-2016-4992 389-ds-base: Information disclosure via repeated use of LDAP ADD operation
• BZ - 1349540 - CVE-2016-5416 389-ds-base: ACI readable by anonymous user
• BZ - 1354331 - Replication changelog can incorrectly skip over updates
• BZ - 1358865 - CVE-2016-5405 389-ds-base: Password verification vulnerable to timing attack
• BZ - 1376676 - Backport AES storage scheme plugin.
• BZ - 1381153 - Crash in import_wait_for_space_in_fifo().

CVEs

• CVE-2016-4992
• CVE-2016-5405
• CVE-2016-5416

References

• https://access.redhat.com/security/updates/classification/#moderate