Juice Jacking: Charging Your Phone Could Be Putting Your Personal Information at Risk

August 24, 2023 8 min read

juice jacking

Hitting the road or catching a flight soon?

If so, you'll probably be carrying your essential portable devices, such as your  phone or laptop.

At some point, you'll need to charge those devices.

However, your device recharging strategy could put your cybersecurity at risk.

The U.S. Federal Communications Commission (FCC) recently released an advisory warning about "juice jacking," an attack that potentially allows cyberattacks to occur silently on your mobile device while it's being charged via a USB cable.

Additionally, the FBI has expressed concerns about these risks.

In a report from the FBI's Denver office, it says, “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 charger and USB cord and use an electrical outlet instead.”

FBI Denver on Twitter 

Based on the 2022 USB Threat Report  from Honeywell Forge, the threats intended to spread through USB or distinctively utilize USB for infection have seen a significant increase, surging up to 52% over four years.
In the ever-evolving landscape of cybersecurity threats, staying vigilant against new dangers is crucial. Juice jacking is just the latest tactic we need to guard against—the future will bring others. Prioritize your digital security when traveling; after all, a drained battery should be the only inconvenience stemming from your travel device charging needs. This technique begins innocently enough. Picture this: you're traveling, your phone battery is critically low, and you spot a free USB charging station at an airport or in a hotel lobby. You plug in, relieved. Unbeknownst to you may have just set off a significant cybersecurity threat.

Attackers exploiting the convenience of these charging spots have found a way to install malware onto public USB charging stations.

The moment you connect your device, they gain unauthorized access to it. The malware installed via this unsecured USB port can stealthily extract personal data and passwords.

This term entered the tech vocabulary around 2011 thanks to Brian Krebs, a cybersecurity journalist. He ran an experiment at DEFCON, a famous hacking conference, where he set up a free charging kiosk. When device owners connected their phones, a message flashed up, essentially saying: "Never trust a public charging station. Data could be stolen or dumped without your knowledge.”

Krebs also notes how Juice Jacking is back and gaining popularity

The Technique Explained

Have you ever noticed how your phone lets you move files back and forth with your computer when you plug it into a USB port to charge? This is because a USB port isn't just a simple power plug.

Picture a usual USB connector as a tiny powerhouse with five pins, even though it only needs one to feed your phone with power. The other two are used for data transfer, and the remaining two are used as an attached device presence indicator and the ground, respectively.


Typically, when a phone is connected to an external device, its operating system automatically turns off data transmission capabilities. You've likely seen a message pop up on your screen asking you to "trust" the computer to which you are connecting. If you give "trust" clearance, data transmission is enabled. However, if you do not grant this clearance or neglect the prompt, your phone will not proceed with data transfers—unless you unknowingly plug into a contaminated public charging station.


Rogue USB ports are rigged to quietly override your phone's protection, activating data transfer modes upon connection. You will not receive any alerts or notifications to signal this is taking place. Once your phone is disconnected, you could unknowingly become a victim of data theft, and your device could potentially become infected with a virus or other form of malware—an unfortunate scenario, indeed.


So, you're wondering how juice jacking comes to life, right? Well, let me take you on a little journey into the somewhat darker side of tech.

 

The Crafting Phase


Picture this; our hacker sets their sights on an ordinary USB charging port and decides to give it a secret double life - not just a benign power provider, but also a data port in disguise! This can be achieved by planting additional hardware or software into this seemingly innocent charging port or even creating a whole new corrupted charging station from scratch.


Loading The Ammo


Their port is no longer just a charging station—it's now an attack tool. They then have to decide on their weapon of choice: perhaps a system for copying and stealing data (giving them instant access to some juicy information), malware that will sneak its way onto unsuspecting devices, or premium-grade ransomware that will lock up victims' devices until a ransom is paid.

Bad actors employ various tampering techniques to compromise charging stations and execute malware installation. Here are a few commonly used methods:


Hardware modification: Attackers physically modify the USB ports of charging stations by adding or altering components. This modification allows them to transfer data alongside the power connection.


Cable interception: Malicious individuals intercept legitimate charging cables or create their own deceptive ones. These cables may look normal, but they contain hidden modifications that enable data transfer or malware installation.


Malicious charging adapters: In some cases, attackers replace genuine charging adapters with their own compromised versions. These adapters tamper with the power supply to inject malware into connected devices.


Planting rogue charging stations: Targeted attacks may involve the installation of fake charging stations in public spaces. These deceptive stations appear authentic but are specifically designed to infect connected devices with malware.
These tampering techniques exploit the trust users have in public charging stations and put their devices at risk.


The Trap Is Set

Next step is to find the perfect hunting ground—a place where desperate people, running low on battery, congregate and will gratefully charge their devices without asking questions. Places like coffee shops, airports, or bustling shopping centers fit the bill perfectly.


Biting The Bait

Finally, along comes an unsuspecting device owner, their battery bar dwindling. They plug into the secretly compromised charging station, offering up their data on a platter or unknowingly allowing the malware an open door into their device.

Yes, some juice hackers take things to another level, fabricating cunningly convincing knock-off charging stations or mastering the art of manufacturing tampered cables, complete with built-in attack tools.

This saga underlines the importance of avoiding publicly offered free juice whenever possible, as the price can sometimes be ridiculously high. Always be a little skeptical and protect your device!

So, how can you protect yourself from juice jacking while traveling?

 

Types of attacks

 

Data Theft Juice Jacking Attack

This attack aims to pilfer personal data from unsuspecting users. The actual data theft happens quickly and automatically. This could even result in your credit cards, email, or health records being compromised.

 

Malware/Virus Infection Juice Jacking Attack

This particular attack allows malware or viruses to be uploaded onto your device. The repercussions could be data loss, loss of functionality, random network connections, device slowdown, and the installation of further malware. 

 

Multi-Device Juice Jacking Attack

This is essentially a malware/virus infection attack but with added oomph. The malware loaded onto your device can infect the other USB charging ports on the charging station, increasing the scale of attacks and compromising multiple devices.

 

Disabling Juice Jacking Attack

As the name suggests, this assault renders your mobile phone useless. Malware penetrates your device, disabling it for you but granting total control to the attacker.

 

OMG Cable: A Wolf in Sheep's Clothing

Adding another dimension to the juice jacking threat is the OMG Cable. This innocuous-looking charging cable is a hacker's dream tool and a user's worst nightmare.

The OMG Cable is a seemingly standard USB cable that can charge your device without a hitch. However, it contains an embedded Wi-Fi chip that enables a remote attacker to access your data or even execute commands on your device, all while you're merely charging your device.

Created security researcher MG, this cable is a testament to the sophistication of current hardware hacking techniques. Once plugged into your device, a nearby attacker within Wi-Fi range can access your data, deliver malicious payloads, change your device settings, or even type and execute commands using a virtual keyboard.

 

Here are some points to keep in mind regarding the OMG Cable:

Stealthy Access: What makes the OMG cable so dangerous is its subterfuge. It looks and acts like a regular charging cable until it's used for an attack, making it difficult to notice.

 

Remote Control: An attacker can maintain a safe distance, yet execute commands on your device. The Wi-Fi chip embedded in the OMG cable can connect to local Wi-Fi networks, extending its reach and providing a cover for the attacker.

 

How to Avoid OMG Cable Attacks: The old adage, "Trust, but verify," fits well here. Try to use only cables you have purchased yourself from trustworthy vendors. Be wary of borrowing charging cables from others or using cables provided at public locations.

The advent of the OMG Cable underscores that virtually any device, no matter how mundane, can be transformed into a cyber weapon lurking in your charging cable.

OMG cable attacks

 

Proactive Measures to Defend Against Juice Jacking Attacks:

Pass on Public Charging Stations

First things first - the most foolproof method to avoid a juice jacking scenario is simple - steer clear of public charging stations. Sure, running out of power is a hassle, but it's preferable to losing sensitive data or dealing with malware.

 

Activate Device Security Measures

Use security measures available on your devices when the situation demands the use of public charging stations. Disable the option that triggers automatic data transfers once connected. Lock your device once charging begins and be sure to deny permission for data transfers when the 'trust this computer' prompt appears. You may also choose to switch your device off before charging.

 

Carry Backup

Keep an extra cable and charger handy to use in a wall outlet when necessary. Alternatively, carry USB batteries or a backup battery, if that suits your device type. This will save you from being tethered to a public charging station and avert potential risks.

 

Invest in a USB Passthrough Device

This is a small, flash drive-esque device that you connect your USB cable to. It works by disabling the data pins in the USB cable, thus preventing data from being transmitted over that cable. Alternatively, you can use a USB charging cable specifically designed to only allow charging. The data transfer pins are either disabled or completely absent in such cables, offering the same protection as USB passthrough devices.

Replace Public Charging Stations with Portable Chargers
Instead of taking the risk with public charging stations, carry a portable charger. It's a much safer option and a valuable investment to safeguard your data.

Conclusion

As we tread deeper into our digital age, cyber threats like juice jacking continue to loom large.

The reality is that our indispensable gadgets are also targets for cunning attackers, exploiting our reliance on them and seizing our vulnerability in moments of need such as a dwindling battery.

One can only expect these risks to multiply, shapeshift, and resurface under new guises such as juice jacking, as we propel towards an increasingly connected future.

While the convenience of plugging in virtually anywhere to power our devices can be convenient, every 'free' power source could come at an unseen cost.

Our defenses must be multi-pronged - sidestepping public charging ports, employing our device security measures, investing in hardware that safeguards data transfer, and carrying power sources like portable chargers.

In essence, the power to protect our data rests in our hands. A cyber threat like juice jacking isn't merely an external hazard, but a stern reminder of the collective responsibility we bear.

As we carry our devices into new terrain, let's be skeptical and most importantly, secure.

So, let's forge ahead, with our guard up and battery full,

Don't let your next charge be your data's downfall!