Guenichi won the gold medal at the Arab Games last year in the men's Greco-Roman 130kg category.
"Guenichi was banned for deliberately not complying with anti-doping testers," the Tunisian federation technical director Montaser Obaidi told Reuters on Wednesday.
"Last November, the testers came to his room at the elite training centre and he refused to open his door and after several hours only provided them with a urine sample, which returned negative.
Obaidi added that Guenichi was then handed a provisional four-month suspension and the 25-year-old took part in an Olympic qualifying tournament in Egypt, where he punched his ticket for Paris 2024.
However, WADA appealed against the lifting of the ban to CAS, Obaidi said.
Images emerged this week of Israel's flagbearer at the Olympic Games, Peter Paltchik, reportedly having signed bombings targeting civilians in Gaza.
A post he had shared on his social media platform resurfaced, showing images of rockets set for Gaza, captioned by the 32-year-old, originally Ukrainian: "From me to you with pleasure".
It came amid global calls for the exclusion of Israeli athletes from the Olympic games in Paris over Israel's brutal offensive on Gaza, which has been described as a "genocide" by rights groups and experts.
Israel's delegation, which headed to France on Monday ahead of Friday's opening ceremony, is being tightly protected in the French capital.
Iran strongly condemned the "reception and protection" of Israeli athletes in a post on X by the country's foreign ministry.
"Announcing the reception and protection of the apartheid terrorist Zionist regime's delegation means giving legitimacy to the child killers," the post said.
"They do not deserve to be present at the Paris Olympics because of the war against the innocent people of Gaza," it added, calling on organisers to ban Israel.
At least 39,100 Palestinians have been killed by Israel's relentless onslaught of the besieged enclave, most of which were women and children.
Israel has been accused of genocide at the International Court of Justice, which ordered Tel Aviv to immediately halt its attacks in the southern city of Rafah, where more than one million Palestinians had sought refuge from the war before it was invaded on May 6.
Israel national anthem jeered during first Olympic match against Mali Israel’s national anthem during the country’s first event at the Olympics was booed by spectators during a football match against Mali at Paris’ Parc des Princes on Wednesday.
Additional security was deployed for the game, amid tensions surrounding Israel’s participation in the Games as the country continues to wage a deadly war in the Gaza Strip.
Israel’s national anthem was jeered by several sections in the half-empty stadium prior to kick-off, while a group of spectators could be seen protesting Israel’s war in Gaza by wearing t-shirts with initials spelling out 'Free Palestine' .
In another instance, Palestinian flags were waved in one of the stadium’s sections, before one was snatched away by an Israel supporter.
The match was attended by French Interior Minister Gerald Darmanin , who spoke to police prior to -kick-off, and said their deployment was “necessary in order to ensure we are there for sport”.
The game ended 1-1, following an own goal by Hamidou Diallo in the match’s first half before Cheickna Doumbia equalised in Mali’s net to salvage a draw.
Israel’s presence at the Olympic Games has been criticised by pro-Palestinian activists and the Palestinian Olympic Committee, due to Israel’s months-long military operation in Gaza, which has killed at least 39,175 Palestinians since 7 October.
The Palestinian Committee called for the banning of Israeli athletes at the Games and decried the double standards from the International Olympic Committee (IOC) over its decision to allow Israelis to compete , as the country's army has killed over 400 athletes in its military offensive.
"The Israelis or the Israeli Olympic Committee have lost the moral, sports, humanitarian and legal right to participate," Jibril Rajoub, the Palestinian Olympic head said.
