On the day of the business trip, he temporarily asked his wife to help transfer some funds. When the plane landed and he opened his wallet, he saw—it's all zeroed out. On the other end of the phone, his wife’s choking voice came through: "I didn't actually make a transfer, I just pasted the mnemonic..." When he turned around to check, the 3 million USDT was gone without a trace.

This isn't a staged act; it's a real story. And behind this story lies a complete chain of hacker attacks.

His wife's device was riddled with issues: the mnemonic was in WeChat chat logs, her old phone's password was never changed, the home WiFi was still using the default password from installation, and she had installed some "Financial Assistant" browser plugin. This seemingly simple "combo" allowed hackers to monitor her clipboard continuously. The moment she pasted the mnemonic, the hackers were already waiting. The assets disappeared silently, and not even the transfer records could be found.

You might think this is too far-fetched. But according to public case statistics, about 70% of digital asset theft cases point to one common problem: improper storage of mnemonics.

**So, what should we do? There are three essential steps:**

**First: Treat your mnemonic as your life**

Not just words. Write it down on a metal plate or a dedicated mnemonic card—absolutely no digital storage like phones, computers, cloud drives, or screenshots. This step may seem redundant, but it blocks 70% of risks. If you're still storing it in your phone's notes app, I suggest stopping immediately and handling it properly.

**Second: Use a "clean" device to operate your wallet**

A "clean" device means dedicated solely for crypto management. Don't install those random "market helpers," "financial tools," or browser plugins. Avoid using public WiFi or cafe computers. Does this sound troublesome? Compared to the heartbreak of theft, a little inconvenience is nothing.

**Third: Someone must be present when family members operate the wallet**

If family help is necessary (like inheritance issues or trusted transfers), start a live video call, verify the recipient's address by checking the last four digits together before transferring, and confirm personally at the end. An extra layer of verification can prevent many accidents.

There’s also a detail worth noting: hacker servers usually clear logs every 72 hours. That means, by the time you realize you’ve been robbed, the critical evidence chain has long disappeared. This is why many people report thefts afterward but find it difficult to recover their assets.

Start acting now. Check where your mnemonic is stored, whether you want to uninstall suspicious browser plugins, and share this knowledge with those around you. Because in the crypto world, security issues are not just technical—they often reflect your daily habits. Your caution with assets is actually the strongest defense against malicious attacks.