Bug#481655: ksmserver crashes on some generic nmap scans

Package: kdebase-workspace-bin
Version: 4:4.0.72-1
Severity: grave

Hello,

as discussed on the IRC channel, here's the IRC log of the bug
discussion (cut out all unnecessary parts):

<the-me> hmm I've found a cute error with KDE4. I'm just running amarok
and listening to the music. everytime I scan this host from another with
for example: nmap -v -A -p1-65500 <desthost>, plasma and ksmserv are
crashing if nmap reaches this port: 46829/tcp open  unknown
* the-me tests now if it will appear without amarok, too
<the-me> now at this port: 51184/tcp open  unknown
<the-me> nevermind, servicescanning about nmap isn't needed to reproduce it.
<the-me> I don't want to restart this system now (for testing) - could
anyone reproduce it?
<MoDaX> the-me: kde has not opened any ports here
<the-me> MoDaX:
<the-me> tcp        0      0 0.0.0.0:37347           0.0.0.0:*
     LISTEN      1000       20150       6189/ksmserver
<the-me> udp        0      0 0.0.0.0:177             0.0.0.0:*
                 0          19792       6075/kdm
<the-me> but while ksmserver and plasma is crashing, I think the first
one it the evil listening
<the-me> yes, it's definitly the ksmserve one.
<the-me> nmap: 37347/tcp open  unknown => crashed.
<the-me> after it crashed and I started kde4 again, ksmserver is