Journal of Cybersecurity and Information Management JCIM 2690-6775 2769-7851 10.54216/JCIM https://www.americaspg.com/journals/show/2747 2019 2019 University Of Anbar, College Of Computer Sciences and Information Technology, Anbar, Ramadi, 31001, IRAQ Sura Sura University Of Anbar, College Of Computer Sciences and Information Technology, Anbar, Ramadi, 31001, IRAQ Rihab .. University Of Anbar, Center for Continuing Education, Anbar, Ramadi, 31001, IRAQ AbdulRahman Kareem .. University Of Anbar, College Of Islamic Sciences, Anbar, Ramadi, 31001, IRAQ Nadia Mohammed University Of Anbar, College Of Computer Sciences and Information Technology, Anbar, Ramadi, 31001, IRAQ Yaqeen .. University Of Anbar, College Of Computer Sciences and Information Technology, Anbar, Ramadi, 31001, IRAQ Ali Makki King Abdulaziz University, KAU, Jeddah, 22233, SAUDI ARABIA Ibrahiem El Emary RC4 is one of the most widely used stream cipher algorithms. It is fast, easy and suitable for hardware and software. It is used in various applications, but it has a weakness in the distribution of generated key bytes. The first few bytes of Pseudo-Random Generation Algorithm (PRGA) key stream are biased or attached to some private key bytes and thus the analysis of key stream bytes makes it potential to attack RC4, and there is connection between the key stream bytes that make it weak and breakable by single- and double-byte biases attack. This work shows the analysis of RC4 key stream based on its non-consecutive double byte biases by using newly designed algorithm that calculates the bias in a standard time (seconds). The results are shown that the bias of RC4 keystream is proved and got the same results that were shown in the literature with less time and discover a set of new non-consecutive double byte biases in the positions (i) and (i+n). The analysis of 256 positions is required additional requirements such as supercomputer and the message passing interface environment that are not available in Iraq, therefore; the analysis is done for 32 positions. 2024 2024 75 83 10.54216/JCIM.130206 https://www.americaspg.com/articleinfo/2/show/2747