Cavani is now embroiled in a controversy over a questionable social media post.
Cavani netted an opportunist 71st-minute equaliser after Allan Saint-Maximin gave the home side a seventh-minute lead with a fine individual effort, side-stepping two markers before he fired past De Gea.
United issued a statement defending the striker, saying there was no malicious intent behind Cavani's message.
Cavani suspended by FA for three games over use of racial term
Edinson Cavani's potential absence for Uruguay would be a severe blow to their hopes of beating France in the World Cup quarter-finals, according to his former team mate and French midfielder Blaise Matuidi.
Images from Sunday's action in the Premier League.
Forwards Kylian Mbappe and Edinson Cavani have been ruled out for Paris St Germain's opening Champions League group stage match against Real Madrid on Wednesday, the French Ligue 1 champions said.
United are 16th in the standings with a game in hand heading into the international break.
Cavani, 31, scored two goals in the Round of 16 win over Portugal, then limped off with a calf injury and has been fighting to get fit in time for the showdown in Nizhny Novgorod.
Uruguay's Edinson Cavani has always played second fiddle to his more illustrious attacking colleagues at country or club level but the long-haired marksman emerged out of those shadows with his twin strike in the World Cup round of 16 last week.
Uruguay forward Edinson Cavani scored twice to earn the South Americans a 2-1 win over European champions Portugal in their World Cup round of 16 clash on Saturday and set up a quarter-final against France.
Uruguay's FA will raise a formal complaint against Chilean defender Gonzalo Jara for provoking striker Edinson Cavani by sticking his finger up his backside during the hosts' 1-0 Copa America quarter-final win.
Edinson Cavani silenced his critics when he scored four goals in Paris St Germain's 6-0 victory at Caen in Ligue 1 on Friday.
Striker Edinson Cavani scored a superb hat-trick to give Napoli a 3-1 home win over defending Serie A champions AC Milan on Sunday.
Paris St Germain achieved a unique domestic treble when Edinson Cavani's goal secured a 1-0 French Cup final victory over Ligue 2 team AJ Auxerre on Saturday.
Paris St Germain took a big step towards the Ligue 1 title when Edinson Cavani's hat-trick inspired them.
Paris St Germain's Zlatan Ibrahimovic and Edinson Cavani each scored twice in a 4-0 win over Bastia as their reshuffled side opened up a three-point lead at the top of Ligue 1 on Saturday.
German club Mainz 05 are ready to offload Gonzalo Jara after the Chile international whipped up a storm at the Copa America by sticking his finger up the backside of an opponent before falling to the floor theatrically when the player retaliated.
Paris St Germain have signed last season's Serie A top scorer Edinson Cavani from Napoli on a five-year contract, the French Ligue 1 champions said on Tuesday.
While their nearest chasers lost, Olympique Lyonnais succumbing 2-1 at home to struggling Lille and Monaco falling 1-0 at Nantes after a last-gasp Lucas Lima thunderbolt, PSG marched on without ever hitting top gear.
Paris St Germain collected their first trophy of the season when Edinson Cavani's double secured a 2-1 victory against Olympique Lyon in the French League Cup final on Saturday.
A late header from Edinson Cavani gave Uruguay a 1-0 win over Copa America holders Chile which saw them snatch top spot in Group C at their opponents' expense and set up a quarter-final meeting with Peru.
Paris St Germain substitute Edinson Cavani, criticised by French media lacking composure in front of goal, responded in style to earn a 2-1 home win over Chelsea in their Champions League last-16 first leg on Tuesday.
News of all that's transpired on and off the football field
Edinson Cavani enjoyed a memorable comeback after spending four weeks on the sidelines with a thigh injury as he scored in Paris St Germain's 2-0 win over Olympique Marseille on Sunday to help his side move eight points clear at the top of Ligue 1.
A summary of sports events and sports persons, who made news on Tuesday
Paris Saint-Germain took a crucial advantage after beating Chelsea 2-1 in an entertaining UEFA Champions League Round of 16 first leg tie at the Parc des Princes in Paris on Tuesday.
FIFA also opened proceedings against the Uruguayan Football Association (AUF) over potential breaches of fair play rules.
FIFA launched proceedings against the players who angrily harangued the referee after crashing out of the tournament in Qatar, despite beating Ghana 2-0 in their final group match on December 2.
Five-times European champions Barca, with their trident of Lionel Messi, Luis Suarez and Neymar subdued, have not exited in the last 16 since going out to Liverpool in the 2006/07 season and the score equalled their worst Champions league loss.
Paris St Germain closed out the year on a high as they maintained their five-point advantage at the top of the table.
IMAGES from the FIFA World Cup Group H match played between Uruguay and South Korea at Education City Stadium in Al Rayyan, Qatar on Thursday
Decisions about the availability of Otavio, who started against Ghana, and reserve left back Nuno Mendes, who is also an injury concern, would be taken after a training session later on Sunday, Santos said.
Bruno Fernandes and Edinson Cavani scored twice each as Manchester United took a giant step towards the Europa League final with a 6-2 drubbing of AS Roma in their semi-final first leg at Old Trafford on Thursday.
Images from the English Premier League matches played on Saturday.
United are four points behind fourth-placed Arsenal, with a game in hand, as they search for a way into the top four and a place in next season's Champions League.
Martin Caceres shackled Son, harassing the South Korean winger any time he got the ball and sticking close to him to discourage others from passing his way.
Edinson Cavani and Anthony Martial struck late goals as Manchester United claimed a scrappy 2-0 victory over Everton at a bitterly cold Goodison Park,
IMAGES from the English Premier League matches played on Sunday.
After a tense encounter finished 1-1 following extra time, Villareal's Rulli stepped up after every on-field player scored their spot kicks and he comfortably beat Spaniard De Gea