rundll32.exe high network usage, should I get worried?


Jul 17, 2013
I was playing games with a friend online and I started lagging heavily. We started the usual routine of alt-tabbing and checking our task manager to see whose fault it was and I noticed rundll32 (location: /Windows/system32, on W8.1) was at high disk and network usage. Things stabilized after a while but it still was sketchy, especially because I just rebooted my PC beforehand and it took slightly longer to do so and a weird process popped out for a second.

I checked the filepath of rundll32 and it has a weird icon I've never seen before: . Am I under risk the genuine process got hijacked?

For whatever it's worth I think my protection is pretty good, I use javascript managers and adblocker on most sites, and I never visit anything sketchy on top of frequent Avira and MB scans.


Sep 21, 2007

rundll32.exe can be used in windows background programs and this I think this is normal.

When windows search for updates, it slow down the computer and
rundll32.exe can be involved.

Could be also other programs.

I would be concern only if it happens all the time or periodically.

To be safe, I would run adwcleaner => JRT and roguekiller from bleepingcomputer to see if you have any malware / virus.