-
30 Days of Code [Day 1]
QUESTION : POW(X,N) CODE: #define vi vector<int> #define pii pair<int, int> #define pb push_back #define mp make_pair #define all(v) v.begin(), v.end() #define fo(i,s,n) for(int i=s;i<n;++i) #define of(i,s,n) for(int i=s-1;i>=n;--i) #define printv(v) for(auto &x : v){cout<<x<<" ";}cout<<endl; class Solution { public: double myPow(double x, int n) { double t; if(!n) return...
-
RSA with C
RSA RSA (Rivest–Shamir–Adleman) is a public-key cryptosystem that is widely used for secure data transmission. p,q are distinct primes. n = p*q phi = (p-1)*(q-1) e is such that 1 < e < phi and is coprime to phi. d = modInverse(e) Mod Inverse Public Key pair (n,e) Private Key...
-
Flag Pwnable.kr challenge writeup
DESCRIPTION Papa brought me a packed present! let's open it. Download : http://pwnable.kr/bin/flag This is reversing task. all you need is binary root@kali:~/rev/pwnablekr# file flag flag: ELF 64-bit LSB executable, x86-64, version 1 (GNU/Linux), statically linked, no section header EXECUTING root@kali:~/rev/pwnablekr# ./flag I will malloc() and strcpy the flag there....
-
ORW Pwnable.kr challenge writeup
Question Description orw [100 pts] Read the flag from /home/orw/flag. Only open read write syscall are allowed to use. nc chall.pwnable.tw 10001 root@kali:~/rev/pwanable# ./orw Give my your shellcode:ok Segmentation fault lets analyze binary with radare2 root@kali:~/rev/pwanable# r2 orw -- ♥ -- [0x080483d0]> aaa [x] Analyze all flags starting with sym....
-
START Pwnable.kr challenge writeup
Lets look at the file. root@kali:~/rev/pwanable/start# file start start: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), statically linked, not stripped lets run the binary root@kali:~/rev/pwanable/start# ./start Let's start the CTF:ok root@kali:~/rev/pwanable/start# let’s analyse the binary with gdb root@kali:~/rev/pwanable/start# gdb -q ./start Reading symbols from ./start... (No debugging symbols...
-
Pin Ctf Learn Rev Eng
PIN Can you crack my pin? link to file We just have to crack the pin thats all root@kali:~/rev/ctflearn/rev# ./rev1 Masukan PIN = 1234 PIN salah ! So we need to get a pin which will print something rather than PIN salah ! 1st Analysed the file with gdb ,...
-
Format String Vulnerability
FORMAT STRING A format string is an ASCIIZ string used to specify and control the representation of different variables int i; printf("%d", i); A format function uses the format string to convert C data types into a string representation …->The format string controls the format function ……..->of variables ……..->representation of...
-
RET2LIBC
A “return-to-libc” attack is a computer security attack usually starting with a buffer overflow in which a subroutine return address on a call stack is replaced by an address of a subroutine that is already present in the process’ executable memory, bypassing the no-execute bit feature (if present) and ridding...