British Open champion Smith rolled in his eighth birdie on the 18th hole at sun-drenched Royal Queensland to move to a nine-under total of 133 at the A$2 million ($1.35 million) event co-sanctioned by Europe's DP World Tour.
Scrivener, who co-led overnight with Min Woo Lee and John Lyras, put together a bogey-free round of 67.
Big crowds have flocked to the course to welcome Brisbane native Smith and compatriot Adam Scott, the former Masters champion, in their return to Australia after nearly three years blighted by the COVID-19 pandemic.
Smith said the crowds were great but not so much for his father, who could barely see him play.
"It seemed like they were three or four deep down either side of the fairway all day," Smith told reporters.
"My old boy was whingeing actually at me yesterday saying that he didn’t get to watch me play golf."
Scott, who trailed the leaders by a stroke overnight after an opening 66, tumbled down the leaderboard with a one-over 72 to be four-under at the halfway mark, six shots behind Scrivener.
After going 16 holes without a birdie, Scott drained a monster putt on the 17th and played up his celebrations to the delight of a roaring gallery, spreading his arms wide and giving a big fist-pump.
"I didn’t sniff anything all day, nothing was good and I find my element in a bunch of drunk Queenslanders," he joked.
"It’s all good fun."
Japan's Masahiro Kawamura shot a 66 to move up to joint third on eight-under with Australian Cameron John, two strokes off the lead.
