Description
30 Points Link
Another PHP type juggling
Statement
Find a way to get the flag.
No bruteforce needed.
Challenge
In this challenge we are giving a web server with php in the backend and an nginx not vulnerable server with 2 input fields
one with a seed and the other is a hash.
We are also giving the source code which is displayed below :
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Unbreakable Random
source code
First thing i noticed was the loose comparison on line
46 and line 47.
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if[$s != false && $h != false] {
if[$s.$r == $h] {
and as the challenge describe, this is our entry point.
Understanding the code
Let’s take a look at what this code does.
First let’s check the functions provided with the source code.
First Function
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function gen_secured_random[] { // cause random is the way
$a = rand[1337,2600]*42;
$b = rand[1879,1955]*42;
$a
Chủ Đề