Last month, I posted a warning about a "hacker" that was targeting pony artists in order to dupe them into opening a virus. In the warning, I mentioned that these sort of warnings normally show up in the form of chainletters meant to implicate and harass others... so I've decided to post a notice about the signs of a fake hacker .
If you are told that merely being +watch'd by a user will get you hacked, it's fake. Doubly so if you are told that being +watch'd will get the people YOU watch hacked. This also applies to messaging services and social networking site, where the "warning" will say instead that getting a friend request will get you hacked and accepting the friend request will get your friends hacked.
If you are told that blocking someone will stop you from getting hacked at all, but doesn't specify the types of messages they send their victims, or are told to block multiple accounts at once that seem to be significantly different people, it's fake. Blocking stops people from sending you messages from the blocked accounts, but that only guards against hackers who work through sending their victims rotten links. A hacker who can guess or force a password can still guess or force your password regardless of whether you've blocked their account or not, and don't even need to have
an account to get into yours.
If you are told to copy/paste anything to protect yourself, or to forward the message to a specific number of people or "as many people as possible," it's fake. Just like telling people that there's a bear on the loose won't stop the bear from mauling you, telling people there's a hacker won't make your account any more secure.
If the message is similar/identical to previous messages you've seen about other hackers, it's definitely a fake. Every year I see one or two "warnings" about hackers that - aside from the alleged hacker's username - are completely identical to chainletters I've been seeing for the past twenty years. Take it from your Internet Grandma, kiddos: new hackers require new warnings, not the exact same one you've gotten about every hacker since 1995.
If the message tells you to actively confront the hacker, it's a fake. You don't combat a hacker by drawing attention to yourself unless you are physically in their presence, and even then, it's best if you buy some new sunglasses and brush up on your kung-fu beforehand.
Just like you shouldn't trust a message that says "OMG LITERALLY EVERYONE WITH THE USERNAME DUDEFARTPICKLEBUTT ON ANY WEBSITE EVERY IS A HACKER BLOCK HIM OR HE'LL GET YOUR STEPMOM'S BOSS'S CREDIT CARD NUMBER!!!!" you also shouldn't trust a message that says "hey, I'm concerned that this person might be a hacker" unless the evidence backs it up.
If you are given specific behaviors to look out for, given the option to decide for yourself whether to block or not, and the warning uses calm, relatively neutral language focusing on the situation as a whole rather than just the username, it's probably legitimate. PROBABLY. Always look into the situation as deeply as you can by yourself, and ask yourself how well you trust the person the warning came from. Your personal judgment is important when somebody you don't know says you're at risk.
And on that note, don't spread warnings you don't believe absolutely. Your best defenses against a hacker are skepticism and a strong password, not blindly repeating the things you hear about hackers.
And, since I've seen this happen before...
If the "hacker" confesses all over the victim's account but not their own, it's fake. A hacker who's willing to identify themselves wouldn't be arguing with an account they control
over whether they had hacked that account or not.
Likewise, a hacker who's willing to identify themselves has probably been signed into their own account recently - always be suspicious when warned that somebody who hasn't been online in over a month is an immediate threat.
If a "victim" calls on people to help them "take down" the hacker, it's fake. Hackers are taken down by presenting evidence to the site staff, not by sending hordes of people after the hacker. Harassing someone into deactivating their account is only a victory for the person trying to frame them - the "victim."
One of the artists I used to watch got hacked. There was no warning beforehand. The hacker was never identified. The user's entire gallery was deleted. The hacker began endlessly uploading porn until the account was banned. The artist was held accountable for the porn, because even if it's been taken from you, your account - and everything posted to it - is your responsibility.