The clip, obtained by The Sun, sees the engaged Carla Connor star canoodling with married co-star Mikey, who plays Gary Windass on the ITV soap.
The video comes amid claims Alison was "rowdy" at the event on Tuesday.
Mikey, who joined Corrie in 2006, is married to wife Rachael Isherwood.
The pair share two children together - son Archie and daughter Eliza.
Meanwhile, Alison, 46, confirmed she was engaged to IT salesman David Stuckey back in September last year.
Alison told OK! Magazine at the time: "It was just a few days after our one-year anniversary.
"I had an inkling he was going to pop the question because he kept putting something on my finger and going: ‘Right, close your eyes and forget this ever happened!’
"We’d also discussed marriage, too. I think we both went from, ‘No, we don’t ever need to get married,’ to, ‘Oh, we really want to get married!’."
The couple were on holiday in Portugal when David popped the question during a romantic sunset cruise.
Alison said she thought he might be planning to pop the question so brought along a Rolex she had got him as an engagement present.
The Leicester-born star has been on Corrie since 2006 also, previously having roles in Brookside, Cold Feet and Holby City.
Coronation Street returns to ITV on Monday, airing at 7:30pm and 8:30pm