How to Check If Your Accounts Were Sold on the Dark Web and Secure Them

Major 2020 Data‑Breach Incidents (Domestic)

Weibo data of 538 million users sold on the dark web.

Personal information of over 6,000 patients from Qingdao Jiaozhou Central Hospital leaked.

Bilibili creator "Dangmei" lost hundreds of gigabytes of video material.

Thousands of university student records exposed across multiple campuses.

A Zhejiang bank fined ¥300,000 for leaking customer data.

More than 50 million personal records from Nantong, Jiangsu sold on the dark web.

Construction Bank employee sold over 50,000 client records.

Major 2020 Data‑Breach Incidents (International)

Nearly 500,000 servers, routers and IoT devices had passwords exposed.

Estée Lauder leaked 440 million sensitive user records due to insecure servers.

Israel’s voter database of 6.4 million citizens compromised.

2.67 billion Facebook accounts listed for sale on the dark web.

Thailand’s largest mobile carrier exposed 8.3 billion user data records.

EasyJet suffered a cyber‑attack leaking 9 million customer records.

Adult website disclosed over 10 billion sensitive user records.

Verifying Account Exposure with HaveIBeenPwned

Visit https://haveibeenpwned.com/ and enter an email address. The service checks more than 470 breach sources and over 10 billion compromised accounts.

The interface uses red highlights to indicate that credentials have been found in a breach; green indicates no exposure.

If a breach is detected, the site lists the specific services where the data appeared.

Risk of Password Reuse

When a password is reused across multiple sites, a single breach enables credential‑stuffing attacks that scan the internet for matching accounts, leading to mass exposure and sale on underground markets.

Mitigation Strategies

Use a unique password for each service. If remembering many passwords is difficult, adopt a reputable password manager:

KeePass : free, open‑source, highly compatible.

LastPass : strong cross‑browser synchronization.

1Password : cross‑platform with high user approval.

Regularly check email addresses on HaveIBeenPwned and update any compromised passwords immediately.