Air carrier Captain reported being notified by the lead Flight Attendant of a fume event during descent. Flight crew continued to the destination airport where a safe landing was executed.

Narrative

During descent around FL180; the lead FA (Flight Attendant) called us to report a dirty socks smell in the aft cabin. She said multiple FAs and passengers smelled it; and passengers were concerned. We put on our oxygen masks; turned on Engine Anti-Ice; and shut off Pack 2 per COM. I [requested priority handling]; got cleared direct to the FAF; and requested paramedics meet us at the gate in case anyone was feeling unwell. The FO (First Officer) called the lead FA back; and she said the smell stopped; so we took off our oxygen masks. There was never any smell in the cockpit. The FO coordinated with Operations to ensure we had an open gate; and advised Dispatch via ACARS. Everything was in place to allow us to park immediately and deplane normally. I requested the ground crew not connect the air conditioning. Paramedics and Airport Rescue and Fire Fighting boarded the aircraft; but no one requested medical assistance. After all the passengers were off; the whole crew debriefed with Airport Rescue and Fire Fighting and local Maintenance. At this time; the FAs said there was a passenger who took their shoes off. They said it was possible this may have been the source of the smell; but they weren't sure. They said the smell was pervasive in the cabin; but did not seem to be coming from the air vents.I wrote up a discrepancy in the logbook and filled out a Cabin Odor Reporting Sheet. I called Maintenance Control; Dispatch; and the Chief Pilot to report the event.