Creating Arbitrary Shellcode In Unicode Expanded Strings
by Chris Anley - An NGSSoftware Insight Security Research Publication
The paper is intended to be read by the portion of the security community responsible for creating protective mechanisms to guard against "shellcode" type security flaws; the intention is to remove the perception that Unicode buffer overflows are non exploitable and thereby improve the general state of network security. It is often the case that several classes of overflow or format string bug are labelled "denial of service" attacks when in fact it is possible to execute arbitrary code. This paper deals with one of these classes of overflow.

This paper introduces a technique (the "Venetian" exploit) that can be used to permit the execution of a small amount of arbitrary code in a situation where a buffer overflow occurs in a "Unicode" string on the Intel x86 processors. This situation is common in the Windows operating systems but the technique is not operating system specific. how this problem can be overcome, using a technique not dissimilar to the "bridge building" method that can be used to create exploit code using only printable ASCII characters.

Download the paper in PDF format here.

Spotlight

The synergy of hackers and tools at the Black Hat Arsenal

Posted on 27 August 2014.  |  Tucked away from the glamour of the vendor booths and the large presentation rooms filled with rockstar sessions, was the Arsenal - a place where developers were able to present their security tools and grow their community.


Weekly newsletter

Reading our newsletter every Monday will keep you up-to-date with security news.
  



Daily digest

Receive a daily digest of the latest security news.
  

DON'T
MISS

Fri, Aug 29th
    COPYRIGHT 1998-2014 BY HELP NET SECURITY.   // READ OUR PRIVACY POLICY // ABOUT US // ADVERTISE //