A message promoting weight loss popped up on the the Confessions of a Shopaholic star's page, and Ritter was unimpressed that her account had been illegally accessed.
In a series of posts, she writes, "Sorry peeps! My Twitter got hacked!!! Don't click on anything saying you can lose 5 lbs. I didn't post that. It's a hacker!"
Ritter is the latest star to have her account hacked - Mark Ruffalo, Australian singer Peter Andre and pop star Ke$ha have all had their Twitter accounts improperly accessed in the last month.