BOSTON, April 16 (Reuters) - American Funds, one of the largest U.S. mutual funds families, sent an email to 825,000 shareholders on Wednesday, advising them to change their passwords, citing "a very narrow window of risk" related to the Heartbleed Internet threat.
American funds spokesman Chuck Freadhoff said that the firm issued the notice "out of an abundance of caution" after learning that one of its vendors had been affected by Heartbleed.
"We have no evidence or belief that any information was used to gain access to any shareholders account," he said.
He declined to name the vendor. (Reporting by Jim Finkle. Editing by Richard Valdmanis)