Vulnerability Note VU#505564

IBM SecureWay Directory is vulnerable to denial-of-service attacks via LDAP handling code

Original Release date: 16 Jul 2001 | Last revised: 12 Dec 2002


The IBM SecureWay Directory contains vulnerabilities that may allow denial-of-service attacks, unauthorized privileged access, or both. These vulnerabilities were revealed using the PROTOS LDAPv3 test suite and are documented in CERT Advisory CA-2001-18. If your site uses this product, the CERT/CC encourages you to follow the advice provided below.


The IBM SecureWay Directory server contains one or more buffer overflow vulnerabilities in the code that processes LDAP requests. These vulnerabilities were discovered independently by IBM using the PROTOS LDAPv3 test suite.


These vulnerabilities allow a remote attacker to crash affected SecureWay Directory servers, resulting in a denial-of-service condition. It is not known at this time whether these vulnerabilities will allow a remote attacker to execute arbitrary code. These vulnerabilities exist on the Solaris and Windows 2000 platforms but are not present under Windows NT, AIX, and AIX with SSL.


Apply a patch from your vendor

Please consult the vendor section for vendor-specific information on addressing this vulnerability.

Block access to directory services at network perimeter

As a temporary measure, it is possible to limit the scope of these vulnerabilities by blocking access to directory services at the network perimeter. Please note that this workaround does not protect vulnerable products from internal attacks.

            ldap    389/tcp     # Lightweight Directory Access Protocol
            ldap    389/udp     # Lightweight Directory Access Protocol
            ldaps   636/tcp     # ldap protocol over TLS/SSL (was sldap)
            ldaps   636/udp     # ldap protocol over TLS/SSL (was sldap)

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
IBMAffected01 Jun 200120 May 2002
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



The CERT Coordination Center thanks the Oulu University Secure Programming Group for reporting these vulnerabilities to us, for their detailed technical analyses, and for their assistance in preparing this document.

This document was written by Jeffrey P. Lanza.

Other Information

  • CVE IDs: CAN-2001-1309
  • CERT Advisory: CA-2001-18
  • Date Public: 16 Jul 2001
  • Date First Published: 16 Jul 2001
  • Date Last Updated: 12 Dec 2002
  • Severity Metric: 4.96
  • Document Revision: 36


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