by wishi » Mon Dec 21, 2009 7:45 pm
There're ways to set obscure defauls like different TTLs or something to make (Nmap) OS fingerprinting harder. However the sophistication of the tools, speaking of p0f or active fingerprinting like in Nmap and other scanners, is not kiddy-level. I don't see many reasons in general to hide system's OSes. First of all you will not be able to archive that in a way that really hides your (potentially) vulnerable entry-points. But furthermore you waste a hell lot of time better used to patch that stuff ;).