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at 1/28/2024 07:30:00 PM

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.

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at 1/28/2024 10:57:00 AM

Are you tired of reading endless news stories about ethical hacking and not really knowing what that means? Let's change that!

This Post is for the people that:

Have No Experience With Cybersecurity (Ethical Hacking)
Have Limited Experience.
Those That Just Can't Get A Break

OK, let's dive into the post and suggest some ways that you can get ahead in Cybersecurity.

I receive many messages on how to become a hacker. "I'm a beginner in hacking, how should I start?" or "I want to be able to hack my friend's Facebook account" are some of the more frequent queries. Hacking is a skill. And you must remember that if you want to learn hacking solely for the fun of hacking into your friend's Facebook account or email, things will not work out for you. You should decide to learn hacking because of your fascination for technology and your desire to be an expert in computer systems. Its time to change the color of your hat 😀

I've had my good share of Hats. Black, white or sometimes a blackish shade of grey. The darker it gets, the more fun you have.

If you have no experience don't worry. We ALL had to start somewhere, and we ALL needed help to get where we are today. No one is an island and no one is born with all the necessary skills. Period.OK, so you have zero experience and limited skills…my advice in this instance is that you teach yourself some absolute fundamentals.

Let's get this party started.

What is hacking?

Hacking is identifying weakness and vulnerabilities of some system and gaining access with it.

Hacker gets unauthorized access by targeting system while ethical hacker have an official permission in a lawful and legitimate manner to assess the security posture of a target system(s)

There's some types of hackers, a bit of "terminology".
White hat — ethical hacker.
Black hat — classical hacker, get unauthorized access.
Grey hat — person who gets unauthorized access but reveals the weaknesses to the company.
Script kiddie — person with no technical skills just used pre-made tools.
Hacktivist — person who hacks for some idea and leaves some messages. For example strike against copyright.

Skills required to become ethical hacker.

Curosity anf exploration
Operating System
Fundamentals of Networking

*Note this sites

Related news

at 1/28/2024 02:24:00 AM

"DirBuster is a multi threaded java application designed to brute force directories and files names on web/application servers. Often is the case now of what looks like a web server in a state of default installation is actually not, and has pages and applications hidden within. DirBuster attempts to find these. However tools of this nature are often as only good as the directory and file list they come with. A different approach was taken to generating this. The list was generated from scratch, by crawling the Internet and collecting the directory and files that are actually used by developers! DirBuster comes a total of 9 different lists (Further information can be found below), this makes DirBuster extremely effective at finding those hidden files and directories. And if that was not enough DirBuster also has the option to perform a pure brute force, which leaves the hidden directories and files nowhere to hide! If you have the time ;) " read more...

Download: https://sourceforge.net/projects/dirbuster

Sunday, January 28, 2024

Vlang Binary Debugging

Related links

How To Start | How To Become An Ethical Hacker

Related news

DirBuster: Brute Force Web Directories

More info

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