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.

More info

1. Hacker Tools For Pc
2. Blackhat Hacker Tools
3. Hacking Apps
4. Hacker Tools Github
5. Pentest Tools Download
6. Nsa Hack Tools Download
7. Tools For Hacker
8. Nsa Hack Tools
9. What Are Hacking Tools
10. Hack Website Online Tool
11. Hack Tools For Windows
12. Pentest Tools Free
13. Pentest Tools Windows
14. Hacking Tools For Mac
15. How To Hack
16. Hacking Tools For Mac
17. Pentest Tools Open Source
18. Github Hacking Tools
19. Black Hat Hacker Tools
20. Growth Hacker Tools
21. Hack Tools For Ubuntu
22. Hacker Tools Linux
23. Hack And Tools
24. Pentest Tools Website Vulnerability
25. Pentest Tools For Mac
26. Pentest Tools Online
27. Hacking Tools 2019
28. Github Hacking Tools
29. Hacker Tools 2019
30. Pentest Tools Tcp Port Scanner
31. Hacking Tools Github
32. Hack Tools For Windows
33. Hacker Tools Online
34. Growth Hacker Tools
35. Pentest Tools Port Scanner
36. Pentest Tools Apk
37. Pentest Tools Find Subdomains
38. New Hacker Tools
39. Pentest Tools Website Vulnerability
40. Pentest Tools Subdomain
41. Pentest Tools Kali Linux
42. Tools 4 Hack
43. How To Hack
44. Hacking App
45. Hacker Tools Free
46. How To Hack
47. Hacker Hardware Tools
48. Pentest Tools Download
49. Hacking Tools Hardware
50. Pentest Tools Review
51. Hacking Tools For Mac
52. Tools For Hacker
53. Hacking Tools And Software
54. Hack And Tools
55. Bluetooth Hacking Tools Kali
56. Hacking Tools Download
57. Hack Tools Github
58. Hacker Tools Windows
59. Pentest Reporting Tools
60. Hacking Tools Kit
61. Hacking Tools Mac
62. Hacking Apps
63. Hackrf Tools
64. Pentest Tools Apk
65. Hacking Tools
66. Hacking Tools Hardware
67. Hacker Hardware Tools
68. Best Hacking Tools 2020
69. Hack Tool Apk
70. Hacking Tools For Games
71. Hack Tools 2019
72. Easy Hack Tools
73. Best Hacking Tools 2020
74. Pentest Tools Open Source
75. Hacking Tools For Windows Free Download
76. Hacker Tools Github
77. Easy Hack Tools
78. Hacking Tools Online
79. Hacking Tools For Kali Linux
80. Hacking Tools Windows 10
81. Physical Pentest Tools
82. Hack Tools For Games
83. Hacking Tools Windows 10
84. Hacker Tools Github
85. Pentest Tools For Android
86. Best Pentesting Tools 2018
87. Pentest Tools Apk
88. Hackrf Tools
89. Usb Pentest Tools
90. Tools Used For Hacking
91. Hack Tools Online
92. Pentest Tools Github
93. Pentest Tools Subdomain
94. Hacking Tools Kit
95. Pentest Tools Windows
96. How To Hack
97. Pentest Tools Android
98. Pentest Tools Nmap
99. Hacks And Tools
100. Hack Tools
101. Best Pentesting Tools 2018