An exfohazard is a piece of information that can cause harm if shared, for instance, the genetic code for a deadly virus. Exfohazards are often considered a type of infohazard, and as of 2026, the words are used somewhat interchangeably. In this post, Yudkowsky suggests that we only use "exfohazard" to refer to information that causes harm when shared, and reserve the word "infohazard" for information that is directly harmful to the bearer, i.e. information that you as an individual would not want to hear.
One should be cautious when discussing these.
Examples and discussion:
See also: