When you’re out and about and your phone is about to die, finding a public charging station can feel like a miracle.

But now, the FBI is warning cell phone users to steer clear of these seemingly helpful stations as they might be rife with bad intentions.

On Twitter, the FBI in Denver told social media users that plugging in devices at these stations can lead to “bad actors” installing “malware and monitoring software” on those devices.

Avoid using free charging stations in airports, hotels or shopping centers. Bad actors have figured out ways to use public USB ports to introduce malware and monitoring software onto devices. Carry your own charger and USB cord and use an electrical outlet instead. pic.twitter.com/9T62SYen9T

— FBI Denver (@FBIDenver) April 6, 2023

“Avoid using free charging stations in airports, hotels or shopping centers,” the agency said via Twitter. “Carry your own charger and USB cord and use an electrical outlet instead.”

This means that hackers can find a way to either disrupt (and essentially crash) a user’s entire interface or, even worse, install software that will give the hackers access to the same interface, including personal data.

The issue is part of a larger type of crime called “juice jacking,” which the Federal Communications Commission has warned consumers about since 2021.

“Cybersecurity experts have warned that criminals can load malware onto public USB charging stations to maliciously access electronic devices while they are being charged,” the FCC warned. “Malware installed through a dirty USB port can lock a device or export personal data and passwords directly to the perpetrator. Criminals can use that information to access online accounts or sell it to other bad actors.”

The agency also noted that sometimes hackers will give cables as promotional gifts as a way to trick consumers into using the charging cords.