Editing Shellcode (section)

==Platforms==
Most shellcode is written in [[machine code]] because of the low level at which the vulnerability being exploited gives an attacker access to the process. Shellcode is therefore often created to target one specific combination of [[Central processing unit|processor]], [[operating system]] and [[service pack]], called a [[Platform (computing)|platform]]. For some exploits, due to the constraints put on the shellcode by the target process, a very specific shellcode must be created. However, it is not impossible for one shellcode to work for multiple exploits, service packs, operating systems and even processors.<ref name="Eugene_2001">{{cite web |title=Architecture Spanning Shellcode |author=eugene |publisher=Phrack Inc. |work=Phrack |date=2001-08-11 |volume=0x0b |issue=57 |id=#0x0e of 0x12 |url=http://www.phrack.org/issues.html?issue=57&id=14#article |access-date=2008-02-29 |url-status=live |archive-url=https://web.archive.org/web/20211109173710/http://phrack.org/issues/57/14.html#article |archive-date=2021-11-09}}</ref><ref name="Nemo_2005">{{cite web |title=OSX - Multi arch shellcode. |author=nemo |work=[[Full disclosure (mailing list)|Full disclosure]] |date=2005-11-13 |url=https://seclists.org/fulldisclosure/2005/Nov/387 |access-date=2022-05-26 |url-status=live |archive-url=https://web.archive.org/web/20220526191616/https://seclists.org/fulldisclosure/2005/Nov/387 |archive-date=2022-05-26}}</ref><ref name="Cha-Pak-Brumley-Lipton_2010">{{cite conference |title=Platform-Independent Programs |author-first1=Sang Kil |author-last1=Cha |author-first2=Brian |author-last2=Pak |author-first3=David |author-last3=Brumley |author-link3=David Brumley |author-first4=Richard Jay |author-last4=Lipton |author-link4=Richard Jay Lipton |conference=Proceedings of the 17th ACM conference on Computer and Communications Security (CCS'10) |location=Chicago, Illinois, USA |date=2010-10-08 |orig-date=2010-10-04 |publisher=[[Carnegie Mellon University]], Pittsburgh, Pennsylvania, USA / [[Georgia Institute of Technology]], Atlanta, Georgia, USA |isbn=978-1-4503-0244-9 |doi=10.1145/1866307.1866369 |pages=547–558 |url=https://softsec.kaist.ac.kr/~sangkilc/papers/cha-ccs10.pdf |access-date=2022-05-26 |url-status=live |archive-url=https://web.archive.org/web/20220526153147/https://softsec.kaist.ac.kr/~sangkilc/papers/cha-ccs10.pdf |archive-date=2022-05-26}} [https://web.archive.org/web/20220526182333/http://users.ece.cmu.edu/~sangkilc/papers/ccs10-cha.pdf] (12 pages) (See also: [https://security.ece.cmu.edu/pip/index.html])</ref> Such versatility is commonly achieved by creating multiple versions of the shellcode that target the various platforms and creating a header that branches to the correct version for the platform the code is running on. When executed, the code behaves differently for different platforms and executes the right part of the shellcode for the platform it is running on.