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China Software Developer Network

Disclosed Dec 21, 201114 years ago6,000,000 affectedUnverified

Leak exposes usernames and passwords of 6 million Chinese developer site users

User names, passwords and email addresses of more than 6 million users of the China Software Developer Network leaked online on December 21, 2011. Police arrested a suspect surnamed Zeng.

What is known

People affected6,000,000 (as reported by the organization)
DisclosedDec 21, 2011
HappenedDec 21, 2011
AttackHacking
Data exposedEmails, Passwords, Credentials and tokens
SectorTech · CN
StatusUnverified: not yet confirmed by an official notice, a filing or the organization
Check your emailHave I Been Pwned

Sources

Source
Have I Been Pwned: China Software Developer Networkhaveibeenpwned.com · Aggregator
Chinese hacker arrested for leaking 6 million logins - ZDNetweb.archive.org · News

Notices filed

WhereFiledPeople
ResearchtotalDec 21, 20116,000,000
Have I Been Pwnedaccounts in the dataNov 27, 20256,414,990
History of this record
  • 2026-09-25 · source_type: aggregator to press · seed source
  • 2026-09-25 · source_url: https://haveibeenpwned.com/Breach/CSDN to https://web.archive.org/web/20120328065303/http://www.zdnet.com/blog/security/chinese-hacker-arrested-for-leaking-6-million-logins/11064 · seed source
  • 2026-09-25 · country: empty to CN · seed source
  • 2026-09-25 · attack: unknown to hacking · seed source
  • 2026-09-25 · data_types: ["emails","passwords"] to ["emails","passwords","credentials"] · seed source
  • 2026-09-25 · records_basis: hibp to organization · seed source
  • 2026-09-25 · records: 6414990 to 6000000 · seed source
  • 2026-09-25 · disclosed: 2025-11-27 to 2011-12-21 · seed source
  • 2026-09-25 · summary: 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. to User names, passwords and email addresses of more than 6 million users of the China Software Developer Network leaked online on December 21, 2011. Police arrested a suspect surnamed Zeng. · seed source
  • 2026-09-25 · title: empty to Leak exposes usernames and passwords of 6 million Chinese developer site users · seed source
  • 2026-09-25 · added · backfill source

First seen 2026-09-25 (Have I Been Pwned). Record counts are as reported. Not legal advice.

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