Salah turned inside the box and slammed the ball against the crossbar with the rebound hitting Senegal defender Saliou Ciss and rolling into the net for an own-goal.
The eagerly awaited clash was a repeat of the Africa Cup of Nations final last month, which Senegal won 4-2 on penalties in Cameroon after 120 goalless minutes.
Sadio Mane, a Liverpool teammate of Salah and scorer of the winning penalty in the African title decider, was closely guarded by Egypt.
He did have a chance soon after half-time off a Bouna Sarr cross, but a close-range header flew just wide of the post.