added a integer overflow problem, included source and flag but neither of those should be provided to the user

risky-business/description.md

@@ -0,0 +1 @@
+We wanted to branch into the casino business, but human employees are too expensive so we decided to automate it. I feel like we missed something obvious though... Oh well! Here's the binary: [casino](casino) (MZ SHELL SERVER THING)

risky-business/flag.txt

@@ -0,0 +1 @@
+easyctf{m4by3_w3_c0u1d_h4v3_d0n3_th47_b3t7er}

risky-business/grader.py

@@ -0,0 +1,4 @@
+def grade(autogen, key):
+    if key.find("m4by3_w3_c0u1d_h4v3_d0n3_th47_b3t7er") != -1:
+        return True, "Correct!"
+    return False, "Nope!"

risky-business/main.cpp

@@ -0,0 +1,75 @@
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <stdlib.h>
+
+
+bool gamble()
+{
+	if (rand() % 5 == 0)
+	{
+		return true;
+	}
+	return false;
+}
+
+void printflag()
+{
+	std::cout << "Welcome to our exclusive club!" << std::endl;
+	std::ifstream flagI("flag.txt");
+	std::string flag;
+	getline(flagI, flag);
+	flagI.close();
+	std::cout << "Here's our special flag: " << flag << std::endl;
+}
+
+
+int networth = 100000;
+int main()
+{
+	std::cout << "Welcome to the EasyCTF 2017 Casino" << std::endl;
+	std::cout << "Try your luck and gain access to our exclusive club!" << std::endl;
+	while (true)
+	{
+		std::cout << std::endl;
+		std::cout << "Your net worth is: $" << networth << std::endl;
+		if (networth > 2000000000)
+		{
+			printflag();
+			break;
+		}
+		std::cout << "Please enter how much you would like to bet:" << std::endl;
+		std::string tmp;
+		getline(std::cin, tmp);
+		std::stringstream s(tmp);
+		int inp;
+		s >> inp;
+		if (!s.eof() || s.fail())
+		{
+			std::cout << "That was not a valid number :(";
+			continue;
+		}
+		if (inp <= 0)
+		{
+			std::cout << "You must bet a positive amount" << std::endl;
+			continue;
+		}
+		if (inp > 100000000)
+		{
+			std::cout << "Sorry, the most we can allow you to bet is $100,000,000" << std::endl;
+			continue;
+		}
+		if (!gamble())
+		{
+			std::cout << "Sorry, I'm afraid you've lost :(" << std::endl;
+			networth -= inp;
+		}
+		else
+		{
+			std::cout << "Congratulations, you won!" << std::endl;
+			networth += inp;
+		}
+
+	}
+	return 0;
+}

risky-business/problem.yml

@@ -0,0 +1,9 @@
+author: GenericNickname
+title: Risky Business
+hint: I wonder how you could make a lot of money...
+category: Binary Exploitation
+autogen: false
+programming: false
+value: 100
+files:
+  - casino