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- Security Affairs
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- Data breaches, Attacks
Keio, a major Japanese railway operator, was hit by ransomware, disrupting business systems and forcing the company to shut down its network. Keio Corporation, one of Japan’s major private railway operators, was hit by a ransomware attack over the weekend, disrupting some of its business systems. The company detected a system failure early Saturday and…
Think your details were in it?
- Check your email address at Have I Been Pwned – it lists the breaches your details have appeared in.
- Change that service's password, and any other account that used the same one. A password manager makes every password unique.
- Turn on two-step verification, and expect scam messages that quote the leaked details to sound convincing.
More helpHave I Been Pwned (opens in a new tab)NCSC: top tips for staying secure online (opens in a new tab)
Defender’s notebook
The attacker technique behind this story, in MITRE’s terms – and what to check in your own estate.
Data Encrypted for Impact
ImpactWhat a defender checks
- Isolate affected hosts from the network to stop the spread.
- Confirm backups are offline and restorable – then test a restore.
- Hunt for what came first: new admin accounts, disabled security tools, remote-access software.
Build the skillBlue Team Engineer · Incident Management & Response Engineering
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