"We have laws in our country," Clinton told reporters aboard her campaign plane. She said Trump "deliberately flouted" the law and put "his personal and business interests ahead of the laws and the values and the policies of the United States of America".
Meanwhile, the leaked Trump campaign memo marked a new low in a presidential campaign that has already seen policy proposals take a back seat to personal attacks.
It came after Clinton described Trump, the Republican nominee, as a man who "has called women pigs, slobs and dogs".
"Mr Trump has never treated women the way Hillary Clinton and her husband did when they actively worked to destroy Bill Clinton's accusers," read one of the talking points on the memo shown to CNN.
The family of the Republican nominee have repeatedly praised Mr Trump for taking the "high ground" by not mentioning Bill Clinton's numerous marital scandals during this week's presidential debate.
But in the hours and days after the debate - widely acknowledged as Trump's weakest public performance since launching his political career - the presidential nominee's campaign launched a full-throated offensive.
In 2014, Monica Lewinsky criticised Clinton for having a "blame the woman" reaction to her affair with Bill Clinton.
The campaign memo called on supporters to revive this claim, and other old and unsubstantiated allegations of sexual misconduct by Bill Clinton against Paula Jones and other women with whom he had affairs.
"Hillary Clinton bullied and smeared women like Paula Jones, Gennifer Flowers and Monica Lewinsky," it read.
In an interview with Fox and Friends, the conservative television show, David Bossie, Trump's deputy campaign manager, said: "If you look at [Hillary Clinton] being an enabler, really, in the nineties and really attacking these women, it goes against everything that she now tries to spout as a candidate for president." Trump first sought to make Bill Clinton's affairs a campaign issue earlier this year when he called Clinton an "enabler". At that time the Clinton campaign stated Trump was running a "campaign from the gutter".
She has yet to comment on the latest attacks.
But asked about Trump's claim of restraint over Clinton's personal matters at the debate, the Democratic nominee responded: "As I say, he can run his campaign however he chooses, and I will continue to talk about what I want to do for the American people".
She didn't hold back on her attacks over the alleged trade embargo violations, however, saying in a tweet that linked to the Newsweek report that Trump acted "against our nation's interest, all so he could line his own pockets".
Trump hit back, saying he "never did business in Cuba".
"No, I never did anything in Cuba. I never did a deal in Cuba," he told New Hampshire's NH1 News, before criticising the Newsweek reporter, saying he has a "bad reputation".
The magazine studied documents that show the Trump company spent at least US$68,000 ($93,730) in 1998 in Cuba when expenditures in the Caribbean country were illegal without US Government approval.
The payment by Trump Hotels came just before the New York business mogul launched his first bid for the White House, seeking the nomination of the Reform Party.
On the first day of that campaign, Trump reportedly travelled to Miami and spoke to a group of Cuban Americans during which he vowed to maintain the embargo and never spend his or his companies' money in Cuba until Fidel Castro was removed from power. During that meeting he failed to mention the fact that Trump Hotels had already reimbursed its consultants for the money spent on the business trip to Havana.
Newsweek reported that the company did not spend the money directly, opting instead to funnel the funds through a consulting firm - Seven Arrows Investment and Development Corp - with Trump's knowledge to make it appear as if the spending were part of a charitable effort.
A former Trump executive who spoke to the magazine on condition of anonymity said the company did not obtain a government licence for its spending before the trip.
Facing questions about the report, Trump's campaign manager Kellyanne Conway all but acknowledged that his company violated the embargo.
"As I understand from the story, they paid money in 1998," she said on the ABC show The View.
However, the Republican nominee ultimately "decided not to invest there", she added, saying the real estate billionaire has remained "very critical" of Cuba and the Castro regime.
