FGA-2008-23:EMC NetWorker Denial of Service Vulnerability
2008.October.21 

Fortinet's FortiGuard Global Security Research Team Discovers Vulnerability in EMC NetWorker 

Summary:

A resource exhaustion vulnerability exists throughout multiple EMC products through an exploited RPC interface.

Impact:

Denial of service. 

Risk:

Medium

Affected Software:

* NetWorker Server, Storage Node and Client 7.3.x and 7.4, 7.4.1, 7.4.2                                            
* NetWorker Client and Storage Node for Open VMS 7.3.2 ECO6 and earlier                                            
* NetWorker Module for Microsoft Exchange 5.1 and earlier                                                          
* NetWorker Module for Microsoft Applications 2.0 and earlier                                                      
* NetWorker Module for Meditech 2.0 and earlier                                                                    
* NetWorker PowerSnap 2.4 SP1 and earlier                                                                          
                                            

Additional Information:

The RPC interface used by the affected EMC products does not properly enforce bounds checking on a parameter which is used to allocate memory on the heap. The vulnerable NetWorker products use the process "nsrexecd.exe". A remote attacker can exploit this by repeatedly sending requests to the RPC interface, each time allocating more and more memory. Eventually system resources will be exhausted, and denial of service is achieved. 

Solutions:

Use the solution provided by EMC http://powerlink.emc.com/
The FortiGuard Global Security Research Team released a signature "EMC.Products.Malicious.Array.Count.DoS", which covers this specific vulnerability

Fortinet customers who subscribe to Fortinet’s intrusion prevention (IPS) service should be protected against this <vulnerability type>. Fortinet’s IPS service is one component of FortiGuard Subscription Services, which also offer comprehensive solutions such as antivirus, Web content filtering and antispam capabilities. These services enable protection against threats on both application and network layers. FortiGuard Services are continuously updated by the FortiGuard Global Security Research Team, which enables Fortinet to deliver a combination of multi-layered security intelligence and true zero-day protection from new and emerging threats. These updates are delivered to all FortiGate, FortiMail and FortiClient products. Fortinet strictly follows responsible disclosure guidelines to ensure optimum protection during a threat's lifecycle.

References:

http://powerlink.emc.com/
http://www.fortiguardcenter.com/advisory/FGA-2008-23.html

Acknowledgement:

Zhenhua Liu, Xiaopeng Zhang and Junfeng Jia of Fortinet's FortiGuard Global Security Research Team