ZDI-09-067: Novell NetWare NFS Portmapper and RPC Module Stack Overflow Vulnerability

ZDI-09-067: Novell NetWare NFS Portmapper and RPC Module Stack Overflow
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-09-067
September 30, 2009

– Affected Vendors:
Novell

– Affected Products:
Novell Netware

– TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 8280.
For further product information on the TippingPoint IPS, visit:

http://www.tippingpoint.com

– Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Novell Netware NFS Portmapper daemon.
Authentication is not required to exploit this vulnerability.

The specific flaw exists within the processing of CALLIT RPC calls. The
vulnerable daemon explicitly trusts a length field when receiving data
which is later copied into a stack buffer, potentially resulting in a
stack overflow. Successful exploitation of this vulnerability can lead
to remote code execution under the context of the daemon.

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

http://download.novell.com/Download?buildid=DNxmXuyVPuY~

– Disclosure Timeline:
2009-06-23 - Vulnerability reported to vendor
2009-09-30 - Coordinated public release of advisory

– Credit:
This vulnerability was discovered by:
* Nick DeBaggis

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