CVE-2013-4449

A denial of service flaw was found in the way the OpenLDAP server daemon (slapd) performed reference counting when using the rwm (rewrite/remap) overlay. A remote attacker able to query the OpenLDAP server could use this flaw to crash the server by immediately unbinding from the server after sending a search request (CVE-2013-4449).

openldap2 was updated to fix three security issues and one non-security bug.

The following vulnerabilities were fixed:

* A remote attacker could cause a denial of service (slapd crash) by
  unbinding immediately after a search request. (bnc#846389,
  CVE-2013-4449)
* A remote attacker could cause a denial of service through a NULL
  pointer dereference and crash via an empty attribute list in a deref
  control in a search request. (bnc#916897, CVE-2015-1545)
* A remote attacker could cause a denial of service (crash) via a
  crafted search query with a matched values control. (bnc#916914,
  CVE-2015-1546)

The following non-security bug was fixed:

* Prevent connection-0 (internal connection) from showing up in the
  monitor back-end. (bnc#905959)

Security Issues:

* CVE-2015-1546
  <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1546>
* CVE-2015-1545
  <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1545>
* CVE-2013-4449
  <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-4449>

The rwm overlay in OpenLDAP 2.4.23, 2.4.36, and earlier does not properly count references, which allows remote attackers to cause a denial of service (slapd crash) by unbinding immediately after a search request, which triggers rwm_conn_destroy to free the session context while it is being used by rwm_op_search.

It was discovered that OpenLDAP incorrectly handled certain search queries that returned empty attributes. A remote attacker could use this issue to cause OpenLDAP to assert, resulting in a denial of service. This issue only affected Ubuntu 12.04 LTS. (CVE-2012-1164)

Michael Vishchers discovered that OpenLDAP improperly counted references when the rwm overlay was used. A remote attacker could use this issue to cause OpenLDAP to crash, resulting in a denial of service. (CVE-2013-4449)

It was discovered that OpenLDAP incorrectly handled certain empty attribute lists in search requests. A remote attacker could use this issue to cause OpenLDAP to crash, resulting in a denial of service. (CVE-2015-1545)