Mahmoud "Trezeguet" Hassan broke the deadlock in the 69th minute, unleashing an unstoppable strike from inside the area to give Egypt the lead.
Ten minutes later, Liverpool star Mohamed Salah doubled Egypt's advantage, finishing off a perfectly delivered cross from Mahmoud Hamdi.
The victory solidified Egypt's position at the top of Group C, six points clear of their nearest rivals.
With only one point needed from their remaining three matches, the Pharaohs are well-positioned to secure their place in the tournament.
First-half dominance
Egypt controlled the tempo of the game throughout the first half, constantly pressing forward in search of an early goal.
However, Mauritania's resolute defense prevented them from breaking through.
Mohamed Salah forced a brilliant save from Mauritania's goalkeeper Mamadou Diop early on, while Ahmed "Zizo" Sayed's powerful shot from outside the box was also denied.
Mauritania's only real threat came from Aboubacar Kouita, whose free-kick narrowly missed the target.
Second-half breakthrough
The Pharaohs continued their dominance after the break, with Marmoush's shot being saved by Diop.
Egypt's breakthrough came in the 69th minute when Trezeguet converted a cross from Zizo.
Mohamed Salah sealed the victory ten minutes later, finishing off a cross from Hamdi Fathi.
Mauritania pushed forward in search of a consolation goal but were unable to find the net.
Their next match against Mauritania will be a crucial opportunity to clinch qualification.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)
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