China Software Developer Network data breach
From Breaches, in the HARD wiki · Updated
This article is about the December 2011 breach of China Software Developer Network. For every breach, see Breaches.
The China Software Developer Network data breach exposed 6,414,990 accounts from csdn.net in December 2011. The data taken includes passwords, usernames and email addresses.[1]
Have I Been Pwned verified it and added it to its search on 27 Nov 2025, 14 years later. It is the 169th largest of the 618 breaches in HARD’s list.
What was exposed
China Software Developer Network’s breach included 3 kinds of data. What each lets criminals do:
| Data | What it’s used for |
|---|---|
| Passwords | Criminals try leaked passwords on email, banking and shopping sites, because people reuse them. |
| Usernames | Half of a login. With a reused password, it opens other accounts. |
| Email addresses | Expect scam emails that name the company to look genuine. |
What to do
- Check whether you’re in it.Search your email address on Have I Been Pwned. It tells you which breaches it appears in, China Software Developer Network among them, without showing the data.
- Change your China Software Developer Network password.If the account still exists, sign in at China Software Developer Network (csdn.net) and change it.
- Change it anywhere you used the same one.Start with your email, then banking and shopping. Leaked passwords are tried on other sites automatically, within days.
- Use a password manager and two-step sign-in.A different password for every site means one breach can’t open the rest. Two-step sign-in stops a leaked password working on its own.
- Distrust messages that mention China Software Developer Network.Scammers use breach data to sound genuine. Don’t click links in emails or texts about the breach; go to the site yourself.
Timeline
- : the breach, as best it can be dated.
- : Have I Been Pwned verifies the data and adds it to its search, 14 years later.
Breaches often stay hidden for a long time. Until it came out, people in it had no reason to change anything.
Similar breaches
Breaches that leaked the same kinds of data, closest in time:
- Sony, June 2011, 37,103 accounts
- Disqus, July 2012, 18 million accounts
- BookCrossing, November 2012, 1.6 million accounts
- League of Legends, June 2012, 339,487 accounts
- Adobe, October 2013, 152 million accounts
- iMesh, September 2013, 49 million accounts
See Breaches for all 618, and Updates for keeping your devices patched.
References
- ^ Troy Hunt. “China Software Developer Network”, Have I Been Pwned, added 27 Nov 2025. Breach data licensed CC BY 4.0.
External links
- Have I Been Pwned, to check your email address
- csdn.net, China Software Developer Network’s website