The 37-year-old Al Ittihad striker has been linked with a move away from the club after falling out with boss Marcelo Gallardo for failing to report for a training camp.
The 2022 Ballon d'Or winner only signed for the Saudi Pro League side last summer but after scoring 12 goals in 20 games for the reigning champions, Benzema's future in the Middle East is unclear.
Not for the first time, Manchester United have been linked with the five-time Champions League winner as they look to solve their goal scoring issues.
Only three Premier League teams boast a worse return than the Red Devils' 24 goals in 21 league games.
Former United defender Ferdinand has been a long-standing admirer of the Frenchman and although they would again opt for signing aging an striker, he believes the club are not in a place to say no to Benzema.
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When asked if signing the veteran striker would be a positive move for Erik ten Hag's side, Ferdinand told the FIVE YouTube show: "Listen, Benzema, how can you say no?
"We're going back to what we've done before. We've done it with Cristiano [Ronaldo], we've done it with [Radamel] Falcao, we've done it with [Edinson] Cavani, we've done it with Zlatan [Ibrahimovic].
"Can we Afford it? Probably not, that's why I don't see it, I'd be very surprised."
Ferdinand did however point to one potential beneficiary should Benzema secure a shock move to Old Trafford.
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"What I would say is that the one person that needs that [Benzema's arrival] more than anyone else right now is [Rasmus] Hojlund. He needs somebody to look and learn from."
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Hojlund has netted just twice in 16 league games since signing from Atalanta for £72million last August.
The 20-year-old Norwegian has taken the brunt of United's goalscoring woes due to the absence of Anthony Martial and Marcus Rashford's indifferent form.