TMZ broke the story ... someone is shopping footage of the 41-year-old former Polo model pleasuring himself during a recent Internet video chat with a female model.
Tyson went on Twitter yesterday to address the issue with fans ... saying he's "sad but life goes on."
"Don't even faze me" ... Tyson added ... "We all do it, just mine got caught on film."
He also admitted, "Not much of a sex tape lol."
Beckford also got Twitter love from "Transformers" star Tyrese Gibson ... the same guy who he gripes about being confused with on the sex tape.
"What folks don't know is that Tyson opened the door for me to model" ... Tyrese explained.
Tyrese also says the confusion with Tyson has helped him get laid (like these guys need help) ... saying, "I've pulled a few of your fans who thought I was YOU..!! They were too bad to let them go!! Lol!"
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