MyRecon OSINTCit0day
On 4 November 2020, Cit0day was breached. 226,883,414 accounts were exposed, including email addresses, passwords. MyRecon rates it 74/100 — severe. That is roughly everyone in Brazil.
Twenty-three thousand websites. That number is the whole story, because almost none of them are sites you would remember using. The forum you joined once in 2013, the shop that sold one thing you needed, the local club, the game that shut down — small sites with small security budgets, breached individually and unremarkably, then swept into one collection.
Nobody notified anyone. Most of those sites never knew, and a good number no longer existed by the time the collection was published. There is no company here to be accountable, no disclosure statement, and no reset email coming.
The compilation also carried cracked plain-text passwords alongside the hashes, which removes the last bit of friction. If you find yourself in this one, the question is not which site leaked it — that is usually unanswerable — but where else that password was ever used. That is the only question this data makes it possible to act on.
What happened
In November 2020, a collection of more than 23,000 allegedly breached websites known as Cit0day were made available for download on several hacking forums. The data consisted of 226M unique email address alongside password pairs, often represented as both password hashes and the cracked, plain text versions. Independent verification of the data established it contains many legitimate, previously undisclosed breaches. The data was provided to HIBP by dehashed.com.
Breach description from Have I Been Pwned, used under a CC BY 4.0 licence.
Who was behind it
No party has been publicly confirmed as responsible, and this page will not name one. Most breaches are never formally attributed: data surfaces on a forum or inside a combined dump long after the intrusion, and the trail back to a specific actor is rarely made public. Where a group has claimed responsibility it is usually named in the account above — that claim is theirs, not a finding of ours.
What was exposed, and why it matters
- Email addressesThe address becomes a confirmed, active target — expect more phishing, better aimed.
- PasswordsAnyone reusing this password elsewhere has those accounts exposed too — credential stuffing is automated and tries them all within days.
What to do if you were in it
- Change this password anywhere you reused it, starting with your email account — that is the one that can reset all the others.
- Expect better-aimed phishing. A message that already knows your name and where you have an account is the whole point of a breach like this.
Questions people ask about this breach
Was my email address in the Cit0day breach?
Enter it in the box at the top of this page. MyRecon checks it against this breach and every other one on record, and the address is never stored.
What data was leaked in the Cit0day breach?
email addresses, passwords. Each one is explained above, along with what it means for the person it belongs to.
When did it happen, and when did it become public?
The breach is dated 4 November 2020. It was published to Have I Been Pwned on 19 November 2020, a gap of 15 days during which the data was already out.
Is the Cit0day breach real?
It is listed as unverified. The data exists and has been indexed, but it has not been confirmed against the named source, so treat the origin as unproven.
How many people were affected?
226,883,414 accounts. That is roughly everyone in Brazil. That is accounts rather than people — one person often has several.
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Three kinds of content appear on this page and they are kept apart deliberately. The breach description is quoted from Have I Been Pwned under its licence. The severity score, the field-by-field explanation and the advice are computed from the record itself — every sentence derives from a number or a flag in it, which is what stops the analysis drifting from the evidence. Anything under the "MyRecon's take" byline is editorial: our reading of this breach, presented as opinion rather than as a finding.