Emulating Shellcodes - Chapter 1

 There are many basic shellcodes that can be emulated from the beginning from the end providing IOC like where is connecting and so on. But what can we do when the emulation get stuck at some point?

The console has many tools to interact with the emulator like it was a debugger but the shellcode really is not being executed so is safer than a debugger.

target/release/scemu -f ~/Downloads/shellcodes_matched/drv_shellcode.bin -vv 

In some shellcodes the emulator emulates millions of instructions without problem, but in this case at instruction number 176 there is a crash, the [esp + 30h] contain an unexpected 0xffffffff.

There are two ways to trace the memory, tracing all memory operations with -m or inspecting specific place with -i which allow to use registers to express the memory location:

target/release/scemu -f ~/Downloads/shellcodes_matched/drv_shellcode.bin  -i 'dword ptr [esp + 0x30]'

Now we know that in position 174 the value 0xffffffff is set.

But we have more control if we set the console at first instruction with -c 1 and set a memory breakpoint on write.

This "dec" instruction changes the zero for the 0xffffffff, and the instruction 90 is what actually is changing the stack value.

Lets trace the eax register to see if its a kind of counter or what is doing.

target/release/scemu -f ~/Downloads/shellcodes_matched/drv_shellcode.bin  --reg eax 

Eax is not a counter, is getting hardcoded values which is probably an API name:

In this case this shellcode depend on previous states and crash also in the debugger because of  register values. this is just an example of how to operate in cases where is not fully emulated.

In next chapter will see how to unpack and dump to disk using the emulator.

Related news

1. Hacking App
2. Hacks And Tools
3. Pentest Tools For Mac
4. Hacking Tools For Windows
5. Hacking Tools Windows
6. Hacker Tools Github
7. Hack Tools For Games
8. Nsa Hacker Tools
9. Pentest Tools Android
10. Free Pentest Tools For Windows
11. Physical Pentest Tools
12. Best Pentesting Tools 2018
13. Tools Used For Hacking
14. Hacking Tools Kit
15. World No 1 Hacker Software
16. Pentest Tools Review
17. Tools For Hacker
18. Hack Tools
19. Pentest Tools For Windows
20. Pentest Tools Online
21. Hacker Tools
22. Pentest Tools Kali Linux
23. Pentest Tools Online
24. Hacking Tools Pc
25. Hacking Tools Kit
26. Hacker Techniques Tools And Incident Handling
27. Hacking Tools Online
28. Android Hack Tools Github
29. Hack Tools Mac
30. Hacker Security Tools
31. Hacker Tools Software
32. Hacking Tools For Kali Linux
33. Hacker Tools Online
34. Pentest Box Tools Download
35. Hacking Tools For Windows 7
36. Hacking Apps
37. Pentest Tools Windows
38. Hacking Tools For Mac
39. Nsa Hacker Tools
40. Hacking Tools Hardware
41. Github Hacking Tools
42. Hacker Tools Free
43. Top Pentest Tools
44. Tools For Hacker
45. How To Hack
46. Hack Tools For Ubuntu
47. Hacker Tools Windows
48. Hacker Tools Apk Download
49. Pentest Tools Online
50. Hack Tool Apk
51. Hacker Tools 2019
52. Hack Rom Tools
53. Pentest Tools Kali Linux
54. How To Hack
55. What Is Hacking Tools
56. Pentest Box Tools Download
57. Pentest Tools Windows
58. Hacker Tool Kit
59. Hacker Tools Linux
60. Pentest Tools Website Vulnerability
61. Pentest Tools Linux
62. Hacker Hardware Tools
63. Hacker Tools Online
64. Pentest Tools Website
65. Hacker Tools Apk
66. Hacking Tools For Kali Linux
67. What Are Hacking Tools
68. Hacker Techniques Tools And Incident Handling
69. Hacker Tool Kit
70. Nsa Hack Tools Download
71. Best Hacking Tools 2020
72. Hacking Tools Online
73. Hacker Tools Linux
74. Pentest Reporting Tools
75. World No 1 Hacker Software
76. Pentest Tools Android
77. Hacker
78. Game Hacking
79. Hacking Tools For Beginners
80. How To Make Hacking Tools
81. Hack Apps
82. Pentest Tools Apk
83. New Hack Tools
84. Hacker Search Tools
85. Hack App
86. Pentest Tools For Android
87. Install Pentest Tools Ubuntu
88. Hacking Tools For Pc
89. Hacker Tools 2020
90. Hacker Tools Hardware
91. Hack Tools For Pc
92. Hacker Tools For Windows
93. Free Pentest Tools For Windows
94. Termux Hacking Tools 2019
95. Wifi Hacker Tools For Windows
96. Blackhat Hacker Tools
97. Hacking Apps
98. Hacks And Tools
99. Nsa Hacker Tools
100. Kik Hack Tools
101. Hack App
102. New Hack Tools
103. Pentest Tools Linux
104. Hacker Hardware Tools
105. Best Hacking Tools 2020
106. Hacker Techniques Tools And Incident Handling
107. Hacking Tools Usb
108. Hack Tool Apk
109. Hacking Tools For Windows 7
110. Pentest Tools For Android
111. Hack Apps
112. World No 1 Hacker Software
113. How To Install Pentest Tools In Ubuntu
114. Pentest Tools Tcp Port Scanner
115. Hacker Tools List
116. How To Install Pentest Tools In Ubuntu
117. Hacker Tools Linux
118. Best Pentesting Tools 2018
119. Pentest Tools Free
120. Hacking Tools Mac
121. Hack Tools Pc
122. Hacking Tools Online
123. Pentest Tools Review
124. Black Hat Hacker Tools
125. Hack Tools Pc
126. Hacking Tools For Windows Free Download
127. Pentest Tools Apk
128. Top Pentest Tools
129. Hacker Tools
130. Hacker Tools Software
131. Hacking Tools Windows
132. Hack Tools Download
133. Pentest Tools Android
134. Nsa Hack Tools Download
135. Hack Apps
136. Pentest Recon Tools
137. Blackhat Hacker Tools
138. Hacker Tools Apk
139. Hacking Tools Download
140. Hacking Tools Hardware