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22 lines
765 B
Plaintext
22 lines
765 B
Plaintext
former QueSO home page <URL:http://www.apostols.org/projectz/queso/>:
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How we can determine the remote OS using simple tcp packets? Well,
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it's easy, they're packets that don't make any sense, so the RFCs
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don't clearly state what to answer in these kind of situations.
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Facing this ambiguous, each TCP/IP stack takes a different approach
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to the problem, and this way, we get a different response. In some
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cases (like Linux, to name one) some programming mistakes make the OS
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detectable.
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QueSO sends:
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0 SYN * THIS IS VALID, used to verify LISTEN
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1 SYN+ACK
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2 FIN
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3 FIN+ACK
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4 SYN+FIN
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5 PSH
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6 SYN+XXX+YYY * XXX & YYY are unused TCP flags
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All packets have a random seq_num and a 0x0 ack_num.
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