p0f

passive OS fingerprinting tool

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  1. Package version
    p0f-2.0.8p3
  2. Maintainer
    Nigel Taylor

Passive OS fingerprinting technique based on information coming from a
remote host when it establishes a connection to our system. Captured
packets contain enough information to determine the remote OS. Unlike
active scanners like Nmap or QueSO, p0f identifies the remote OS without
sending anything to it.