Aubry, who is also the mayor of Lille, said she would not hesitate to take legal action to stop websites from continuing to spread false information about her and her husband, Jean-Louis Brochen.

“I know everything, I know who is behind it,” she told the Journal du Dimanche newspaper, adding that she had not hesitated to pick up the phone and call those who started rumours about “assumed alcoholism, a claimed brain tumour or imaginary homosexuality.”

She pointed her finger at figures on the right who she said were largely responsible for keeping the rumour mill running, claiming that a highly placed figure in the current government was one source of the muck spreading.

Aubry’s husband, an attorney, has also been a target, especially of several right-wing websites, some associated with the far-right National Front.

Brochen has repeatedly been accused of being an “Islamist” or “Salafist” lawyer after he defended 17 lycée students who wore headscarves in the classroom before France’s law went into effect banning religious symbols in schools.

“I’m not scared of these dirty campaigns,” Aubry said. “I’ve had so many attacks launched against me that I’m well shielded against them.”

However, the right has slammed Aubry for insinuating that it is behind the speculation, accusing the socialists of employing a “new dirty trick” in order to avoid a debate over the substance of Aubry’s candidacy for the presidential primary.

“She’s posturing,” said Christian Jacob, the president of the conservative UMP group in the National Assembly, on Monday.

“The UMP doesn’t play dirty,” said Nadine Morano, a UMP minister for vocational training, adding that Aubry was “pursing a strategy of victimization.”