Operation Endgame 4.0 data breach: 4.3M accounts exposed
Severity: high · Patch status: no-fix-needed · Since 2026-06-18
On 18 June 2026, the latest phase of Operation Endgame targeted the SocGholish malware operation, a prolific malware distribution network used to compromise systems and facilitate further cybercrime. Coordinated by international law enforcement agencies with support from Europol and Eurojust, the operation remediated almost 15,000 compromised websites and disrupted more than 100 servers and domains used to distribute malware. Authorities initially provided HIBP with 154k impacted email addresses and more than half a million previously unseen passwords. The following week, a further 4M email addresses and 9M passwords relating to the StealC malware operation also targeted by Operation Endgame were provided, followed by another 131k email addresses the following month, bringing the total to more than 4.3M unique email addresses. Exposed data: email addresses, passwords. The breach dates from Jun 18, 2026; Have I Been Pwned loaded it on Jun 18, 2026.
What to do
- If you had a Operation Endgame 4.0 account, change its password and the password of any other account that reused it.
- Turn on multi-factor authentication wherever it is offered.
- Check whether your addresses are in this breach at https://haveibeenpwned.com.
- Expect targeted phishing that quotes the leaked details; verify any unexpected contact out of band.
Sources
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