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More than 200 victims of Medusa ransomware identified over the last year, CISA says

CISA and FBI update Medusa ransomware advisory, reporting more than 500 total victims and warning the gang operationalizes newly disclosed exploits within 24 hours.

CISA and the FBI updated their March 2025 advisory, stating Medusa actors had hit more than 500 victims as of April 2026, up from 300 in 2025, with a focus on healthcare and critical infrastructure. The agencies say Medusa rapidly adopts newly announced exploits, sometimes using them up to a week before public vulnerability disclosure, but does not develop its own zero-days, preferring access obtained from unknown sources. The gang moved to an affiliate model in 2023, offers up to $1 million for exclusive initial access brokers, and uses credential stealers plus legitimate remote access tools including AnyDesk, Atera, ConnectWise and Splashtop. No new victims have appeared on its leak site since April, after the shutdown of the University of Mississippi Medical Center drew significant law enforcement attention.

The Record · 29d agoRansomware in the wild1

Medusa ransomware tallies hundreds of new victims, says updated advisory on group’s tactics

CISA, FBI, and HHS updated their Medusa ransomware advisory, reporting over 500 victims and detailing the gang's access-broker and exploit tactics.

A joint advisory update from CISA, the FBI, and HHS expands the March 2025 Medusa guidance, drawing on a year of FBI investigations. The ransomware-as-a-service group's known victim tally grew from more than 300 to more than 500 between March 2025 and April 2026, with the Healthcare and Public Health sector frequently hit. Medusa pays access brokers $100 to $1 million, has exploited flaws such as Fortra GoAnywhere and BeyondTrust vulnerabilities, and leverages newly announced exploits within 24 hours, sometimes a week before public disclosure. The group uses living-off-the-land techniques, remote monitoring and management software, and RDP for lateral movement, and has been linked to actors including Microsoft-tracked Storm-1175 and North Korean hackers targeting healthcare.

CyberScoop · 29d agoRansomware in the wild

ATF confirms cyberattack hit system containing info on its investigation targets

Qilin ransomware group claimed breaching the ATF, exposing data on investigation targets; the agency says a standalone system was hit with no mission impact.

The Bureau of Alcohol, Tobacco, Firearms and Explosives confirmed a cyberattack on a standalone system holding information about targets of ATF investigations, designated a major incident, with no impact on case management, lab, or eForms systems. Qilin, a Russian-speaking affiliate-based ransomware group, claimed responsibility, though ATF declined to confirm involvement or the root cause. Qilin has claimed hundreds of victims across 60+ countries since 2022 and partners with Scattered Spider and Moonstone Sleet.

CyberScoop · 19d agoRansomware in the wild

AI agents carried out every step of this ransomware attack – then left the victim an 80-page security audit

Unit 42 says a human attacker used AI agents to execute a full ransomware intrusion in under 10 hours, leaving the victim an 80-page security audit.

Palo Alto Networks Unit 42 incident responders report a human ransomware operator used frontier AI models and agentic attack frameworks to breach an enterprise in under 10 hours, work that normally takes human operators around two weeks. AI agents performed reconnaissance, breached a public API endpoint to tunnel into the network, scraped code repositories for hard-coded tokens and service passwords, then used them to steal master administrative credentials from the secret-management system for root access. Specialist pivot agents validated access to cloud, identity, CI/CD, container and SaaS environments, and the attacker hijacked CI/CD workflows to steal cloud keys and turn the victim's cloud AI services into post-compromise infrastructure. The agents left an 80-page audit detailing dozens of exploited findings.

The Register · Security · 14d agoRansomware in the wild