Zouma is set to be out for at least two months after suffering a hamstring tendon injury during Saturday’s 3-2 win over his former club Chelsea at the London Stadium.
West Ham are involved in four competitions across that time and Moyes has been left with just Craig Dawson and Issa Diop as his only senior centre-backs across until January.
The club is ready to back Moyes to sign defensive cover as West Ham bid to sustain their top-four push and continue to progress in the Europa League.
Here, Standard Sport assesses three options the Hammers could pursue.
Moyes is a long-term admirer of Tarkowski, who West Ham pushed hard to sign during the 2020 summer transfer window only to have a number of bids knocked back by Burnley.
The 29-year-old, capped twice by England, is out of contract at the end of the season and would be keen to work with Moyes at the London Stadium.
Burnley, though, are believed to still value Tarkowski at up to £20million despite his contract situation, a price West Ham would be unwilling to meet.
Furthermore, there has been no formal approach to Burnley by West Ham and Tarkowski is relaxed about seeing out his contract.
The Liverpool defender was this week compared to Italy legend Franco Baresi by Rio Ferdinand following his performance against AC Milan in the Champions League on Tuesday, which is not a bad reference for the CV.
Phillips was making his first start of the season in the San Siro and the 24-year-old is yet to make an appearance in the Premier League this season.
While Liverpool may be hesitant to strengthen a side pushing for the top four, while also losing some depth in doing so, a decent offer from West Ham and the carrot of regular playing time for Phillips may be enough to swing a deal.
Perhaps the most difficult of these options for Moyes to pursue, should he choose to do so.
Former Chelsea man Ake has long been touted for the top, and joined Manchester City from Bournemouth for £40m in 2020.
While competition is fierce under Pep Guardiola, Ake has started two of the last three games in all competitions and it is unlikely City would be willing to let him go.
The Dutchman is an accomplished defender and fits the bill of Moyes needing someone to step right in with Premier League experience.
The 26-year-old is also left-footed, offering the balance that Moyes wants in his back four.
Convincing City to do business, however, will be some task.