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If you get a security pop-up while you're browsing online alerting you to an unauthorized charge attached to one of your accounts, don't panic, and don't act impulsively. Scammers are currently using these alerts to impersonate Apple and Amazon support (and possibly others) to convince people that their accounts have been compromised and need to be verified to prevent further fraudulent activity. Naturally, this is just a ruse designed to gain access to your device or accounts, which will do far more damage than the fake alert itself.

This campaign, described by Malwarebytes Labs, starts with a browser pop-up that appears on top of Apple's or Amazon's website. The alerts are designed to look like legitimate notifications and state that the user's Apple ID or Amazon account was recently used to make a $149.99 purchase. Targets are urged to call the support number listed—the same on both pop-ups—immediately to prevent further unauthorized activity. The scammer on the other end of the line may try to convince you to download a tool that provides remote access to your device, hand over credentials, or even pay a fee to protect your account.

If you Google the number listed in this specific campaign, you'll find a fake Amazon support website ("amazonhelp[dot]support") set up by fraudsters to make the scheme look more legitimate—of course, the real Amazon customer service site is hosted on amazon.com. Other scam hallmarks present here include manufactured urgency, technical jargon, and a dollar amount that's just enough to get your attention but not so high that it seems like an obvious fake.

First things first: no legitimate company will send you security alerts via browser pop-up. If there's an issue with your account, you may receive an in-app notification or an email, though you should always be wary of the latter, as it's also a common vector for scams. To confirm whether these alerts are real, log into your account by going directly to the website or app and check your message history or activity log.

It's also worth noting that you won't dispute fraudulent charges with customer support over the phone. In fact, you're far more likely to deal with your bank or credit card issuer directly for this, and you may actually get a fraud notification from a financial institution first in the event of a suspicious purchase. Calling a number from a browser pop-up is not the way. Do not give out account information to anyone over the phone unless you have verified the number, such as by clicking through the company's app, and initiated the call yourself.

Finally, these fake pop-ups may be the result of malicious ads, browser redirects, or compromised sites, all of which are used in phishing campaigns. If you're served one, exit the tab immediately and do not click or engage with it further.