Clipboard malware changed my address and stole my Bitcoin

This one is about something I did on my own computer that cost me money even though I did not interact with a scam website directly. It was a silent attack and I did not understand what had happened until it was too late.

I was moving some Bitcoin from a software wallet on my laptop to a hardware wallet for long term storage. I copied the receiving address from my hardware wallet application, opened my desktop wallet, pasted the address into the send field and double checked the first and last few characters. Everything looked fine. I sent roughly 0.3 BTC.

The transaction confirmed on the blockchain as usual, but the funds never showed up in my hardware wallet. I thought maybe I had selected the wrong account, so I checked every one. Nothing. That was the moment panic started to set in.

I went back to the transaction details and copied the recipient address into a text file. Then I compared it to the address I had originally copied from the hardware wallet. The first four characters matched, and the last four matched, but the middle section was completely different. That was when I realised something on my computer had swapped the address after I copied it.

After doing some research I learned about clipboard hijacking malware. Once it is installed on your system, it quietly watches for anything that looks like a crypto address in your clipboard. When it sees one, it replaces it with the attacker’s own address, often designed to look very similar at the start and end so that quick checks do not catch it.

I ran several antivirus and anti-malware tools and sure enough, one of them detected a trojan that had probably come from a cracked software installer I had downloaded weeks earlier. I cleaned the system, but of course the Bitcoin was already long gone through several other wallets.

The whole experience really shook my confidence. I thought that as long as I used non custodial wallets and kept my seed phrase safe, I was in control. I did not realise my own computer could silently sabotage every transaction I made.

Now when I send any significant amount, I do a few extra things. I verify the full address on the hardware wallet screen itself, not just in the software. I send a tiny test amount first and confirm it arrives before sending the rest. And I keep one machine just for financial activity, with no random downloads or experiments.

If you are using copy and paste for wallet addresses on a shared or cluttered computer, please take this seriously. It only takes one infected installer or one shady browser extension to give an attacker control over where your funds actually go.