An attack ad aired during the 2008 Democratic Primaries stated that Hillary Clinton will "say anything and do nothing."
Barack Obama didn't say that Hillary Clinton could not be trusted or that she was not qualified for president.
In July 2016 an image featuring quotes attributed to Barack Obama, uttered in 2008 about his then political opponent Hillary Clinton, was circulated on social media just as Clinton was claiming the 2016 Democratic presidential nomination:
The first half of the quote reproduced in the image, at least, can be loosely attributed to Barack Obama. Although he didn't actually say those words, the phrase "she will say anything and change nothing" was part of a voiceover narration used in a radio spot approved by Obama during the 2008 Democratic primaries:
Obama: "I’m Barack Obama, running for president and I approve this message."
Announcer: "It’s what’s wrong with politics today. Hillary Clinton will say anything to get elected. Now she’s making false attacks on Barack Obama.
"The Washington Post says Clinton isn’t telling the truth. Obama 'did not say that he liked the ideas of Republicans.' In fact, Obama’s led the fight to raise the minimum wage, close corporate tax loopholes and cut taxes for the middle class.
"But it was Hillary Clinton, in an interview with Tom Brokaw, who quote 'paid tribute' to Ronald Reagan’s economic and foreign policy. She championed NAFTA — even though it has cost South Carolina thousands of jobs. And worst of all, it was Hillary Clinton who voted for George Bush’s war in Iraq.
"Hillary Clinton. She’ll say anything, and change nothing. It’s time to turn the page. Paid for by Obama for America."
Although this radio attack ad focused on Clinton's trustworthiness, the phrase "Hillary can't be trusted and isn't qualified to be president" did not appear in it, and we found no record of Barack Obama's having otherwise uttered or used this phrase during the 2008 campaign. Such a charge would also have been problematic for the young Illinois senator to have made during the 2008 election, as back then Obama was seen as the more unqualified and inexperienced candidate compared to Hillary Clinton.
Interestingly, when ABC News covered this ad in 2008, they presciently wrote that it was "so harsh" that they wouldn't be surprised if the GOP eventually used it against Hillary Clinton:
The ad is so harsh, in fact, I wouldn't be surprised to see whomever the GOP nominee ends up being using it in his ads against Clinton, should she become the Democratic nominee.