LinuxQuestions.org - Messages log, strange

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Messages log, strange

Hello,

I am a newbie and have a thing in my messages log I dont understand

As I sit here this is happening over & over again

ar 28 18:51:00 Nickandros su(pam_unix)[2874]: session opened for user myuser by (uid=0)
Mar 28 18:51:00 Nickandros su(pam_unix)[2874]: session closed for user myuser
Mar 28 18:52:00 Nickandros su(pam_unix)[2879]: session opened for user myuser by (uid=0)
Mar 28 18:52:00 Nickandros su(pam_unix)[2879]: session closed for user myuser

Does anyone know what this is?

Thanks

Looks like someone is using "root" and su'ing to your user (err, wait, is it the other way around?)? Any way, if you're not invoking the su command, then someone on your system is. If no one else is supposed to be on your system, then chances are you have an unwelcomed guest.