ZDI-12-011 : Novell Netware XNFS caller_name xdrDecodeString Remote Code Execution Vulnerability

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ZDI-12-011 : Novell Netware XNFS caller_name xdrDecodeString Remote
Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-12-011
January 10, 2012

• – CVE ID:

• – CVSS:
  10, AV:N/AC:L/Au:N/C:C/I:C/A:C

• – 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 11929.
  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. Authentication is not
  required to exploit this vulnerability.

The flaw exists within the xnfs.nlm component which is used when
handling NFS RPC requests. This process listens on UDP port 32779. When
decoding the xdr encoded caller_name from an NLM_TEST procedure request
the process uses the user supplied length as the bounds for its copy to
a stack buffer. A remote attacker can exploit this vulnerability to
execute arbitrary code under the context of the system.

• – Vendor Response:

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

http://download.novell.com/Download?buildid=Cfw1tDezgbw~

• – Disclosure Timeline:
  2011-06-03 - Vulnerability reported to vendor

2012-01-10 - Coordinated public release of advisory

• – Credit:
  This vulnerability was discovered by:

• Francis Provencher for Protek Research Lab's

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