A lot of ppl get confused with this. Background verification is for BOTH. in many cases security takes long time to clear, because it's done by CSIS, CBSA etc.
Criminality is done by RCMP and has a one year validity and gets updated annually and it's very quick gets done online, unless fingerprint was required form the applicant.
In my case Security check took 1.5 year (yes you read right March 2020 - June 2021), during that time I contacted IRCC countless times and they couldn't do anything with my application until Security check is cleared. so if someone stuck with security don't hate on IRCC, they can't process the application with it.
Bottom line if Background in progress it's because either both or one is pending.
hope this clear things.