Hobi dan motivasi

Why vlang? V is a featured, productive, safe and confortable language highly compatible with c, that generates neat binaries with c-speed, the decompilation also seems quite clear as c code.
https://vlang.io/

After open the binary with radare in debug mode "-d" we proceed to do the binary recursive analysis with "aaaa" the more a's the more deep analys.



The function names are modified when the binary is crafted, if we have a function named hello in a module named main we will have the symbol main__hello, but we can locate them quicly thanks to radare's grep done with "~" token in this case applied to the "afl" command which lists all the symbols.


Being in debug mode we can use "d*" commands, for example "db" for breakpointing the function and then "dc" to start or continue execution.


Let's dissasemble the function with "pD" command, it also displays the function variables and arguments as well, note also the xref "call xref from main"


Let's take a look to the function arguments, radare detect's this three 64bits registers used on the function.


Actually the function parameter is rsi that contains a testing html to test the href extraction algorithm.


The string structure is quite simple and it's plenty of implemented methods.




With F8 we can step over the code as we were in ollydbg on linux.


Note the rip marker sliding into the code.


We can recognize the aray creations, and the s.index_after() function used to find substrings since a specific position.


If we take a look de dissasembly we sill see quite a few calls to tos3() functions.
Those functions are involved in string initialization, and implements safety checks.

• tos(string, len)
• tos2(byteptr)
• tos3(charptr)

In this case I have a crash in my V code and I want to know what is crashing, just continue the execution with "dc" and see what poits the rip register.



In visual mode "V" we can see previous instructions to figure out the arguments and state.


We've located the crash on the substring operation which is something like "s2 := s1[a..b]" probably one of the arguments of the substring is out of bounds but luckily the V language has safety checks and is a controlled termination:



Switching the basic block view "space" we can see the execution flow, in this case we know the loops and branches because we have the code but this view also we can see the tos3 parameter "href=" which is useful to locate the position on the code.



When it reach the substr, we can see the parameters with "tab" command.



Looking the implementation the radare parameter calculation is quite exact.


Let's check the param values:


so the indexes are from 0x0e to 0x24 which are inside the buffer, lets continue to next iteration,
if we set a breakpoint and check every iteration, on latest iteration before the crash we have the values 0x2c to 0x70 with overflows the buffer and produces a controlled termination of the v compiled process.





Read more

1. Hack Tool Apk
2. Game Hacking
3. Hacker Search Tools
4. Best Hacking Tools 2020
5. Hacking Tools 2020
6. Pentest Box Tools Download
7. Pentest Reporting Tools
8. Hak5 Tools
9. Pentest Tools List
10. Hack And Tools
11. World No 1 Hacker Software
12. Hack And Tools
13. Pentest Automation Tools
14. Pentest Tools Free
15. Pentest Tools Windows
16. Pentest Reporting Tools
17. Physical Pentest Tools
18. Hack Tools For Windows
19. Hacker Tools Windows
20. Hacking Tools For Windows
21. Hacker Tools
22. Github Hacking Tools
23. Beginner Hacker Tools
24. Pentest Tools List
25. Pentest Tools Bluekeep
26. Hacking Tools For Windows 7
27. Pentest Tools
28. Hacking Tools For Games
29. Tools Used For Hacking
30. Hack Apps
31. Hackers Toolbox
32. Hacks And Tools
33. Pentest Tools Github
34. Hacker Tools
35. Pentest Tools Alternative
36. Github Hacking Tools
37. Hacking Tools Download
38. Hack Tools For Windows
39. Nsa Hacker Tools
40. Hacking Tools For Pc
41. Hack Tool Apk
42. Hacker Security Tools
43. Pentest Tools For Android
44. Tools 4 Hack
45. Hack Tools Download
46. Growth Hacker Tools
47. Pentest Tools Website Vulnerability
48. Pentest Recon Tools
49. Hacker Tools Hardware
50. Hack Tools Github
51. Nsa Hacker Tools
52. Pentest Tools Download
53. Pentest Tools Apk
54. Hacking Tools Hardware
55. What Is Hacking Tools
56. Hack Tool Apk
57. How To Make Hacking Tools
58. Hack Tools For Mac
59. Pentest Tools Download
60. Game Hacking
61. Hack And Tools
62. Hacker Tools Apk Download
63. Hacker Tools For Mac
64. Hacker Tools For Pc
65. Black Hat Hacker Tools
66. Pentest Tools Online
67. Pentest Tools Alternative
68. Hacker Tools Software
69. What Are Hacking Tools
70. Tools For Hacker
71. Hacker Tools
72. Hack Tools For Windows
73. Pentest Tools Kali Linux
74. Best Hacking Tools 2019
75. Hacking Tools 2020
76. Hacker Tools 2019
77. Pentest Tools For Mac
78. Hacker Tools For Ios
79. Hacking Tools For Mac
80. Pentest Tools Url Fuzzer
81. Game Hacking
82. Hacking Tools For Pc
83. Hacking Tools And Software
84. Hackrf Tools
85. Hack Tools Pc
86. Easy Hack Tools
87. Hacker Tools 2019
88. Hack Tools For Ubuntu
89. Pentest Tools Subdomain
90. Hacking Tools Windows
91. Black Hat Hacker Tools
92. Pentest Tools Kali Linux
93. Tools For Hacker
94. Hacking Tools And Software
95. Hack Website Online Tool
96. Free Pentest Tools For Windows
97. Black Hat Hacker Tools
98. Pentest Tools For Android
99. Hacking Apps
100. Hacking Tools Download
101. World No 1 Hacker Software
102. What Is Hacking Tools
103. Nsa Hack Tools Download
104. Hack And Tools
105. Pentest Tools Bluekeep
106. Hacking Tools Online
107. Hak5 Tools
108. Hack Tools For Mac
109. Hacking Tools Free Download
110. Tools Used For Hacking
111. Nsa Hack Tools
112. Pentest Recon Tools
113. Hacking Apps
114. Physical Pentest Tools
115. Pentest Tools Nmap
116. Hacker Security Tools
117. Hacker Tools Mac
118. Hacker Security Tools
119. Hack App
120. Hack Tools For Games
121. Best Hacking Tools 2019
122. Pentest Tools Android
123. Pentest Tools Website Vulnerability
124. Hacker Tools For Ios
125. Hack Tools For Games
126. Hacker Tools Linux
127. Pentest Tools Kali Linux
128. Hacking Tools Pc
129. Hacking Tools Github
130. Hacking Tools Hardware
131. Pentest Tools
132. Pentest Tools Review
133. Hacker Tools Mac
134. Pentest Tools Apk
135. Hack Tools Pc
136. Hacker Techniques Tools And Incident Handling
137. Hacking Tools 2020
138. Hack App
139. Hacker Tools Free Download
140. Hacking Tools For Kali Linux
141. Hackers Toolbox
142. Hacking Apps
143. Black Hat Hacker Tools
144. Pentest Tools Apk
145. Hacking Tools Windows 10
146. Hacker Search Tools
147. Hacker Tools Apk Download
148. Pentest Automation Tools
149. Pentest Tools For Android
150. How To Install Pentest Tools In Ubuntu
151. Hacking Tools For Windows Free Download
152. Pentest Automation Tools
153. Pentest Tools Kali Linux
154. Pentest Tools Find Subdomains

Silahkan sobat tinggalkan komentar jika dirasa ada informasi yang sobat butuhkan