Just got the same "critical" toaster from Software Updater re IE 10 version update needed 10.0.9200.1611 to 10.0.9200.1618. As I have double-checked the validity of the alert using other installed programs, and also Google, and found nothing amiss, have to put this down to a possible erroneous vps update by avast!
I would not do anything with this alert and wait a couple of days to see if anything changes with new vps's coming in later on. No new out-of-band patches for IE 10 have been issued today or in the last few days, and all security updates were released on June 11, 2013 by Microsoft.
Secunia PSI is not yet reporting a critical update for IE 10, and here, as in Software Updater, the .exe is reported as 10.0.9200.1611, but no update is called for or needed. If PSI confirms version .1618 is indeed missing, then and only then would I apply the sub_version update. As Software Updater is still a newer program, I'd wait for Secunia to alert and use that to update IE before I used SU.
All Microsoft Updates were applied successfully on Microsoft Tuesday when they came in.