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high severity December 21, 2011 · 1 min read

China Software Developer Network Data Breach (2011)

If you are a customer of China Software Developer Network, here’s what’s now in circulation.

In 2011, the China Software Developer Network (CSDN) suffered a data breach that exposed over 6M user records. The data included email addresses alongside usernames and plain text passwords.

China Software Developer Network Data Breach (2011)

What the free scan actually returns

Sample resultyou@email.comIllustrative — not a real person

Found on people-search siteswe remove these

These listings are live, public, and legal to remove — and removing them is what we do.

value redacted in this sampleage, relatives, address historySpokeo
value redacted in this samplephone, household, property recordsBeenVerified
value redacted in this sample582 companies checked

Found in breach recordsverifiedreported — unverified

Each record is labeled: confirmed breach data, or an attacker’s claim no one has verified.

verifiedvalue redacted in this samplepassword + phone · 2024telecom breach
unverifiedvalue redacted in this sampleclaimed in ransomware listing · 2026leak-site claim

Leaked data cannot be deleted from the internet — anyone claiming otherwise is lying. Broker listings can be removed. We do the second, and show you exactly what to fix from the first.

Were you a China Software Developer Network customer?
China Software Developer Network is one listing. Your email is probably in others.
6.4M accounts were exposed here. Check whether yours is one — and find every other leak tied to the same address, in about 15 seconds. No account, no card.

By running your scan you agree to the Terms and Conditions and the Privacy Policy, and to GalaxyWarden emailing you the results of this scan.

Report details & sourcing

Severity High
Disclosed December 21, 2011
Last reviewed July 22, 2026
Affected 6.4M
Data exposed Email addressesPasswordsUsernames
By GalaxyWarden Threat Research · Editorial & sourcing standards
Editorial & sourcing policy
GalaxyWarden is a breach-monitoring service and news aggregator. We do not exfiltrate, host, purchase, or redistribute stolen data. Breach information is compiled from publicly accessible sources and threat-intelligence platforms, and is reported as claims attributed to their source. We promptly correct or remove material shown to be inaccurate — see our content & takedown policy or write to support@galaxywarden.com.
Sources: Have I Been Pwned
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