Rating: 3.0
Problem:<span>
JVM</span>(rev, 25 points)
"Bytecodes everywhere, reverse them."
Attachment
rev25_3100aa76fca4432f.zip
Solution:
In the zip file there was a .class file. It can be immediately recognized that this is a Java .class file (the name of the challenge "JVM" is also a hint as it stands for "Java Virtual Machine"), and while the .class file is just the binary, Java (like C# or VB.NET) can easily be decompiled because of how highly detailed the bytecode is. Pop this into a decompiler such as http://www.javadecompilers.com/, and we'll get the following source:
public class EKO {
public static void main(String[] arrstring) {
int n = 0;
for (int i = 0; i < 1337; ++i) {
n += i;
}
String string = "EKO{" + n + "}";
}
}
If we run the source, we'll get our flag.
<span>Flag: EKO{893116}</span>
