News of the French leader's affair with actress Julie Gayet, divulged by Closer magazine in January last year, prompted the 60-year-old to split with his long-term partner Valérie Trierweiler.
On Friday, the glossy weekly published photos of 42-year-old Gayet travelling to the western city of Nantes to visit the set of a film she is producing in a "state-owned car", accompanied by one of the French leader's bodyguards.
"Julie Gayet may not ever have officially appeared on the arm of the president, but it seems she benefits from other privileges linked to her personal relationship with the head of state," the magazine wrote.
"As evidenced by her security worthy of a first lady."
Already in November, celebrity-focused magazine Voici had published pictures of the two looking cosy together inside the Elysée presidential residence, prompting five staff members to be reassigned over what constituted a damaging security breach.
Asked about fresh revelations on Friday that Gayet was benefiting from official security, Hollande's entourage refused to comment.
Public funds for protection?
But the main opposition UMP party latched onto claims made by the magazine, which also says that Gayet and Hollande meet up several times a week and that the actress regularly walks his black Labrador puppy Philae.
"Either Ms Gayet is the president's official partner and in this case, he says it and the state should ensure her protection," Sebastien Huyghe, UMP spokesman, told BFMTV.
"But if that's not the case, there is no reason that public funds should be used to accompany, transport and protect Ms Gayet."
Interviewed on the iTele television channel, Finance Minister Michel Sapin, who is close to Hollande, said potential "threats" could justify these measures.
"When one is in the public (eye), and comments are made on your personal situation, there can be threats," he said.
But asked whether Gayet was being threatened, he said he did not know.
Already the least popular president in modern French history for his failure to revive the economy, Hollande was damaged further by the very public way in which his affair with Gayet and subsequent break-up with Trierweiler played out.
(Trierweiler signs a copy of her book. Photo: AFP)
Trierweiler, a glamorous journalist who had been Hollande's partner for the best part of a decade, went on to write a best-selling kiss-and-tell that savaged the president's personal and political reputation.
She portrayed the unpopular president as a cold-hearted egotist, who was contemptuous of the "toothless" poor.
But Hollande has since risen back up in the popularity ratings for his widely-praised handling of the Paris Islamist attacks last month.
His ties with Gayet can be traced back to at least 2012, when she campaigned for him ahead of the presidential election which brought him to power.
The slender, fresh-faced actress featured in a campaign clip in which she described Hollande as a "humble", "fantastic" man "who is really tuned in".