TippingPoint Zero Day Initiative

Novell eDirectory Server Malformed Index Denial of Service Vulnerability

ZDI-10-189: October 1st, 2010

CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 9971. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows attackers to deny services on vulnerable installations of Novell eDirectory. Authentication is not required in order to trigger this vulnerability.

The flaw exists within Novell's eDirectory Server's NCP implementation which binds, by default, to TCP port 524. While handling a malformed request, the application explicitly trusts a field when translating it to an index into a table of counters. If this index is too large, the application will set a value outside the array and the ndsd process will become unresponsive resulting in an inability to authenticate to that server.

Vendor Response

Novell has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline

    2009-04-28 - Vulnerability reported to vendor
    2010-10-01 - Coordinated public release of advisory


This vulnerability was discovered by: