Lazarus is a name used by security researchers and public authorities for a suspected, loosely defined intrusion set associated with multiple malware and cyber-espionage operations. The label may cover related but not identical activity, and attribution can change as technical evidence is reassessed. Public reporting has connected the name to incidents involving credential theft, malicious software, theft of funds, and disruptive attacks; those reports should not automatically be treated as proof that every campaign sharing similar tooling has the same operator.
For defenders, coverage under this tag is most useful when it identifies the initial access path, affected software, infrastructure, and evidence supporting attribution. Practical priorities include phishing-resistant multifactor authentication for privileged and remote access, prompt remediation of exploited internet-facing systems, application allowlisting for sensitive environments, and monitoring for unusual authentication, scripting, and outbound connections. During a suspected intrusion, preserve endpoint, identity, email, and network logs before containment changes evidence, then scope for stolen credentials and persistence across connected systems.