TippingPoint Zero Day Initiative

Novell Client NWSPOOL.DLL EnumPrinters Stack Overflow Vulnerability

ZDI-08-005: February 11th, 2008


Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 5262, 5266. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on systems with vulnerable installations of the Novell Netware Client. Authentication is not required to exploit this vulnerability.

The specific flaw exists in nwspool.dll which is responsible for handling RPC requests through the spoolss named pipe. The EnumPrinters function exposed by this DLL contains a logical flaw allowing an attacker to bypass a patch introduced to prevent the vulnerability described in ZDI-07-045. Exploitation of this vulnerability leads to arbitrary code execution in the context of the SYSTEM user.

Vendor Response

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

Disclosure Timeline

    2007-12-11 - Vulnerability reported to vendor
    2008-02-11 - Coordinated public release of advisory


This vulnerability was discovered by:
    Anonymous and Avosani Gabriele