Backdoors in the microcode assembly instructions for x86 processors

 3r3195. 3r3-31.
We do not trust the software for a long time, and therefore we carry out its audit, we carry out reverse engineering, we run it step by step, we run it in a sandbox. What about the processor on which our software runs? “We blindly and wholeheartedly trust this little piece of silicon.” However, modern hardware has the same problems as software: secret undocumented functionality, errors, vulnerabilities, malware, trojans, rootkits, backdoors. 3r31-10. 3r3111.  3r3195.
Backdoors in the microcode assembly instructions for x86 processors ISA (Instruction Set Architecture) x86 is one of the longest continuously changing “instruction set architectures” in history. Beginning with the 8086 design, developed in 197? ISA undergoes constant changes and updates; while maintaining backward compatibility and support for the original specification. Over the 40 years of its growth, the ISA architecture has acquired and continues to be overgrown with a multitude of new modes and instruction sets, each of which adds a new layer to the previous design, which is already overloaded. Due to the policy of complete backward compatibility, in modern x86 processors there are even those instructions and modes that are now completely forgotten. As a result, we have a processor architecture, which is a complex intertwining maze of new and ancient technologies. Such an extremely complex environment - raises many problems with the cyber security of the processor. Therefore, x86 processors cannot claim to be the trusted root of critical cyber infrastructure. 3r31-10. Steam Data and Avoid Firewalls . 2017. 3r33180.  3r3195. 3r33175. 3r3176. Daming Chen
. 3r3r1616. Microparse: Microcode parser for AMD, Intel, and VIA processors
//GitHub. 2014. 3r380.  3r3195. 3r33175. 3r3171. Sandsifter: The x86 processor fuzzer
//GitHib. 2017. 3r33180.  3r3195. 3r33175. 3r3176. Karev V.M. 3r33177. 3r3178. How to write in an assembly language program with overlapping instructions (another bytecode obfuscation technique)
//Habrahabr. 2018. URL: (appeal date: October 2? 2018). 3r33180.  3r3195. 3r3182. 3r3191. 3r3191. 3r3191. 3r3195. 3r3195. 3r3188. ! function (e) {function t (t, n) {if (! (n in e)) {for (var r, a = e.document, i = a.scripts, o = i.length; o-- ;) if (-1! == i[o].src.indexOf (t)) {r = i[o]; break} if (! r) {r = a.createElement ("script"), r.type = "text /jаvascript", r.async =! ? r.defer =! ? r.src = t, r.charset = "UTF-8"; var d = function () {var e = a.getElementsByTagName ("script")[0]; e.parentNode.insertBefore (r, e)}; "[object Opera]" == e.opera? a.addEventListener? a.addEventListener ("DOMContentLoaded", d,! 1): e.attachEvent ("onload", d ): d ()}}} t ("//"""_mediator") () (); 3r3189. 3r3195. 3r3191. 3r3195. 3r3195. 3r3195. 3r3195.
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