Cybercriminals posing as the U.S. Postal Service continue to target consumers with phishing emails that claim packages are undeliverable. Then, potential victims are asked to click on fake tracking numbers that could download various forms of malicious software to their computers. This may include ransomware, which can freeze files, photos and other data on a device until a victim coughs up the demanded cash. It could also be spyware, which can track user activity or steal personal and financial data from an infected device. Even more alarming - the emails look authentic. Many come with a USPS logo and fake tracking numbers or bar codes. And hackers aren't just exploiting the U.S. Postal Service - phishing emails posing as UPS, FedEx and DHL have also been reported.Remain wary of emails from unknown sources that ask you to open an attachment or click on a link to learn more about a package delivery. The USPS won't email residents about parcels - the organization will call or leave a notice. Fake package delivery emails often look like this.