Obama slams despicable attack ad against joe biden
I'm not aware of any information that suggests former President Barack Obama has publicly slammed a despicable attack ad against Joe Biden. It's possible that you may be thinking of a different political figure or a different situation.
However, it's worth noting that Joe Biden has been the subject of several attack ads during his presidential campaign, and some of these ads have been criticized for being misleading or unfair. Obama has not publicly commented on these ads, but he has spoken out against the use of negative campaigning and the spread of misinformation in politics.
In a speech at the University of Illinois in August 2018, Obama criticized the use of negative campaigning and the spread of misinformation in politics, saying that it was "a threat to our democracy" and that it was "not who we are as Americans." He also urged politicians to focus on issues and to engage in respectful and constructive debate.
It's possible that Obama may have made similar comments about the attack ads against Biden, but I'm not aware of any specific statement he has made on the topic.