Security issue? Free Public WiFi Ad Hoc network broadcast

["Ken S" <ken.securitylist () gmail com>]

Recently, I noticed an Ad Hoc network broadcast at my company called
"Free Public WiFi".  I thought that was pretty weird, so I used
MiniStumbler to try to find it.  Unfortunately, I couldn't easily tell
which laptop it was.  After a day or two, it went away.

Yesterday, I was at a different building (miles away) and saw the same
thing, except MiniStumbler reported a different MAC for the 2nd
instance.  I saw a thread on Tek-Tips on the same topic, but no one
had an answer.

Any thoughts?   Do I have some compromised machines on my network?

Thanks in advance for your insights.

Ken

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