There's a question about what to do about outdated answers, but what if the answer is not outdated but was always incorrect and gave simply wrong information, or more seriously information that might lead to a serious insecurity in the Stack Exchange user's systems?
For the Server Fault question "Securely add a host (e.g. GitHub) to the SSH known_hosts file" the two top answers are actually insecure. They both involve using ssh-keyscan which is subject to a man-in-the-middle attack (it just downloads the first key it sees). The first and accepted answer does say "verify them manually" so technically it's not truly wrong, but since it doesn't explain how to do that it isn't really answering the question.
This is the top result on the Google search for the subject so it's important that the correct information is surfaced and made more visible.
I do not want to flag the answers since they don't seem to be malicious, so it's not appropriate. I've downvoted the others. How can I get a bit more attention from e.g. moderators to get the insecure answers made less prominent and more clearly warn people about them?