How would you realize that one or more of your Internet accounts—email, social media, financial—have been hacked? (Some prefer the terms “compromised” or “breached”—you may hear them from support techs.) Unfortunately, there’s no telltale warning sign because “hacked” could mean any number of things. Here are some possible indications:

• People you trust report receiving email that you didn’t send.
• Social media friend requests are made to people you don’t know, or messages you don’t recognize are sent from your account.
• Although you’re certain you have the correct password, you can’t log in to an account.
• You become aware of your personal data appearing in places it shouldn’t.
• Unknown charges or transfers appear in a bank or credit card account.

However, attackers will also try to fool you into thinking an account has been compromised to get you to enter passwords or financial information on a website designed to steal data. Don’t assume you’ve been hacked just because you received a phishing email saying so or because you see unexpected notifications claiming your computer is infected. No legitimate entity will ever send such email, and the only notification about malware you should ever see would come from anti-malware software you installed.

(Speaking of malware, dealing with that is a topic for another day—we’re focusing on online accounts in this article. Nonetheless, if one of your accounts has been compromised, it’s also worth scanning your Mac with the free version of Malwarebytes or VirusBarrier Scanner, just in case.)

First off, don’t panic. It’s important to take a deep breath, document everything you see with screenshots (press Command-Shift-5), and move quickly to regain control over whatever accounts were hacked and prevent others from falling prey to the attacker.

When you suspect an account has been compromised, try to verify the problem. Do the following:

• Alert techs: If the account in question is for work, immediately alert your IT department and follow their instructions. If it’s a personal account, contact us. Tell whoever is helping you that you have screenshots you can send and be ready to forward any suspicious messages you have as well.
• Gather evidence: Ask the person who told you about the problem to forward the message they received to another of your email addresses, or to a close friend or family member so you can see what’s being said in your name. Scrutiny of the fake message may reveal information about what has happened, though you may need help from someone with more technical experience.
• Examine email: Since email account breaches are the most concerning (because they can be used to reset passwords elsewhere), scan your email for messages you didn’t send or replies to such messages. Along with the Inbox, look in the Sent mailbox and the Trash. Also, check your settings and filters to ensure incoming messages aren’t being forwarded elsewhere and then deleted.
• Check social media: Connect to all your social media accounts—even those you don’t use regularly—and look for posts, friend requests, messages, or anything else that suggests an attacker has been impersonating you.
• Audit accounts: Log in to important accounts and look for suspicious activity, such as login attempts from unfamiliar locations or IP addresses or changes to account settings.

If you find evidence to suggest that one or more of your accounts have been compromised, follow these steps:

• Immediately change the passwords for any affected accounts. We always recommend using a password manager like 1Password to generate strong, random passwords.
• Whenever possible, turn on two-factor authentication.
• If available for the account in question, follow advice from the service. Apple, Facebook, Google, Instagram, Microsoft, and Twitter all have advice on how to respond, as will many other companies.
• Review account settings for unauthorized changes, especially recovery options like backup phone numbers and email addresses.
• Look through your accounts in your password manager and change the passwords for the most important ones and any that might be related.
• If you can’t get into an account because the password has been changed, make sure you have sole control of your email account and then trigger a password reset.
• For affected financial accounts, along with changing the password, immediately call the institution and ask for their help locking the account to prevent any transfers.
• If your email account was used to send phishing messages to contacts, you should alert any friends, family, and colleagues who might have received the messages that your account was hacked and that the previous message wasn’t from you.

Security breaches are stressful, we know, but it’s imperative that you deal with them right away. The longer you wait, the more damage the attacker can cause, including stealing your money, impersonating you, scamming your friends and family, and compromising your employer’s systems. We’re here to help.

(Featured image by iStock.com/PUGUN SJ)