Why You Should Never Casually Use Free Wi-Fi Abroad (I Only Connect at My Hotel)

How do you handle Wi-Fi when you travel abroad? A lot of people grab "Free Airport WiFi" while waiting for their bags. Connect to a café's free Wi-Fi to post on Instagram, search something on the subway. Most of us hook into public Wi-Fi without much thought.

Personally, I've always found public Wi-Fi a bit unsettling, so I only use my hotel's Wi-Fi — and even there, mostly just for searching. I buy plenty of eSIM data ahead of time and barely connect to Wi-Fi when I'm out and about. It started as just a vague discomfort, but turns out it was actually the right call. Free Wi-Fi abroad is a much more dangerous territory than most people realize.

If you've been connecting to Wi-Fi anywhere without much thought, this one's worth reading.

3 reasons free Wi-Fi abroad is genuinely dangerous

1. Evil Twin — fake Wi-Fi pretending to be the real one

This is the most common trick. Near airports or cafés, hackers set up fake Wi-Fi networks with names nearly identical to the real ones. "Free_Airport_WiFi" might be the real one, while the hacker broadcasts "Free Airport WiFi." A single character difference, or sometimes the exact same name. Almost impossible to tell apart.

The moment you connect, all your data flows through the hacker's equipment before reaching the internet. KakaoTalk messages, Instagram logins, emails, card numbers — everything sits there for them to intercept. This is called a "man-in-the-middle (MITM) attack."

2. Even real Wi-Fi can be eavesdropped from within the network

This is the truly scary part. Even legitimate, official free Wi-Fi isn't safe. Anyone else on the same network, if they have the intent and the skill, can see traffic flowing across that network.

That person at the next table in the café with their laptop open? Could be a hacker. As long as you're on the same Wi-Fi, the data leaving your phone is visible to them. HTTPS (the lock icon in your browser) does encrypt communications properly — but not every app uses it correctly.

3. Just connecting can install malware automatically

This is a more sophisticated technique — some fake Wi-Fi networks install malware on your phone the moment you connect. You might think the internet isn't working and move on to a different Wi-Fi, but by then a malicious app has already been installed in the background and is harvesting your data.

This kind of malware can capture how you use your phone, your keystrokes, even screenshots — and you'd have no idea.

5 things you should never do on public Wi-Fi

If you've connected to free Wi-Fi abroad, never do these 5 things.

  1. Bank app login → full account exposure risk
  2. KakaoTalk new device login → entire Kakao account can get hijacked
  3. Entering card information → hotel bookings, online shopping payments
  4. Email and social media logins → account theft leading to impersonation
  5. Cloud sync → photos and contacts exposed

Searching or pulling up a map is generally fine, but logins and payments should always be done over mobile data (eSIM or roaming). On top of that, I also use incognito mode a lot.

So is hotel Wi-Fi actually okay?

I do use hotel Wi-Fi. Two reasons.

It has a password — hotel Wi-Fi that requires your room number or a separate password is significantly safer than public Wi-Fi. Not just anyone can access it.

The hotel manages it — being a hotel, they pay at least some attention to security. Different story from a café or airport.

That said, hotel Wi-Fi isn't 100% safe either. It's pretty rare, but a hacker among the other guests could still be a threat. So even at the hotel, I stick to searches and maps. Bank apps or KakaoPay I don't even open on hotel Wi-Fi. Those, I always use over eSIM mobile data.

My usual setup looks like this

Whenever I head abroad, I always buy plenty of eSIM data upfront — with a bit of cushion so I don't run out. Looks pricey at first, but since it solves all my security concerns in one move, it's honestly a really cost-effective investment.

My typical pattern:

  • In the hotel: hotel Wi-Fi for searches, maps, YouTube and that's about it
  • Outside: eSIM data for everything (maps, payments, social media)
  • Logins and payments: always over eSIM data (even at the hotel)

A less-known risk — airport USB charging ports

Also worth flagging, even though it's not Wi-Fi. Airport USB charging ports are dangerous too.

It's called Juice Jacking — hackers plant a device on USB ports in airports or other public spaces, and as you charge, they pull data off your phone. The Korea Internet & Security Agency (KISA) has issued warnings about this.

Safe approach:

  • Bring your own charger and use an outlet (not the USB port)
  • Carry a portable battery
  • If you really only have access to a USB port, use a "data-blocker USB adapter"

I can't charge on the plane, so I always carry a portable battery. I use that even after landing, and only plug into an outlet once I'm back at the hotel.

To wrap up

To sum it up: free Wi-Fi abroad is genuinely dangerous.

Evil Twin, man-in-the-middle attacks, automatic malware installation — all three threats are lurking. Light browsing is fine, but logins and payments should never go through public Wi-Fi.

The safest path is honestly just using mobile data through eSIM or roaming. Plenty of people hesitate at the price when shopping for eSIM data, but compared to having your card info stolen, it's a really cheap form of insurance.

I use hotel Wi-Fi only for searches and run everything else over eSIM data — that's the most practical way I've found to actually protect my own information. Don't ever forget: just because Wi-Fi is available doesn't mean it's safe. The risk of getting hacked is real.