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8 stories in the last 30d

Aurora Ransomware Operators Use Cursor AI in Attacks Against 10 Targets

Aurora ransomware operators used Cursor AI running Claude Sonnet to plan and execute intrusions against dozens of organizations in nine countries.

CloudSEK and Gambit Security analyzed exposed infrastructure tied to the Russian-speaking Aurora (Aur0ra) group, revealing months of activity against more than 20 organizations across nine countries between April and July 2026, with 33 victims listed by Ransomware.Live. The operator used the Cursor agentic coding assistant to plan attacks in Russian, including an AD CS exploitation plan, and Gambit observed Cursor Agent (running Anthropic's Claude Sonnet) performing hands-on exploitation tasks such as Nmap scanning, NetExec enumeration, NTLM relay, and certificate attacks against 10 targets. Attacks begin with email bombing plus IT help desk vishing via Xray-core, followed by SMB/LDAP/WinRM/RDP lateral movement, log clearing, Defender disabling, and exfiltration; the Windows and Linux/ESXi encryptors are built from a single Zig codebase, with shadow copy deletion and VM-killing before encryption.

The Hacker News · 16d agoRansomware in the wild1

Rhysida Publishes Berlin Government Data After €2m Extortion Demand Refused

Rhysida published 5.7 TB of Berlin state government data, including sensitive CBRN emergency plans, after the state refused a €2m ransom demand.

The Rhysida ransomware gang leaked roughly 5.7 TB — about 1.4 million files — stolen from Berlin's state network after the government declined to pay 30 bitcoins (about €2m) by the September 4 deadline. The dump reportedly includes sensitive state emergency plans for terrorist attacks and CBRN disaster scenarios in a folder titled 'AG CBRN-Rahmenplanung', plus personnel files, absence lists, payroll data, and home addresses, potentially affecting tens of thousands of people. Berlin says there are no indications the state network remains compromised and will notify affected individuals on a risk-based basis after forensic analysis.

Infosecurity Magazine · 9d agoRansomware

New pro-Ukraine hacker group targets Russian companies with custom ransomware

F6 links new pro-Ukraine ransomware group VantaCore, likely a Thor rebrand, to seven attacks on Russian firms using custom tooling and multimillion-dollar demands.

Russian cybersecurity firm F6 reports that VantaCore, a ransomware group believed to be a rebrand of pro-Ukrainian group Thor, has targeted at least seven Russian organizations with ransom demands reaching millions of dollars, operating as a ransomware-as-a-service operation with a Tor-based victim chat and a leak site. The group uses custom-built tooling including the VantaCore ransomware that encrypts servers and workstations, VantaCoreLoader for distribution, the VantaCoreRAT backdoor, and SnowKiller, which disables antivirus and security software. Initial access relies on poorly secured VPNs and remote-access tools, flaws in internet-facing applications, and credentials stolen from business partners. F6 notes pro-Ukrainian groups increasingly abandoned stock ransomware like LockBit 3 Black and Babuk in 2025-2026 in favor of custom malware.

The Record · 14d agoRansomware

Nutex Health Says Patient Data Stolen, Hackers Threaten Leak

The Gentlemen ransomware gang claims breach of US healthcare provider Nutex Health, exfiltrating patient and employee data and threatening publication.

Nutex Health disclosed in an SEC 8-K filing that an unauthorized third party accessed and exfiltrated patient, employee, credentialed provider, business, and financial data from company servers, and threatened to publish it. The Gentlemen ransomware group listed Nutex on its leak site; a class action was filed August 27 and Edelson Lechtzin LLP is separately investigating. Nutex operates over 27 facilities in 12 states and served nearly 100,000 patients in the first half of 2026, with no material operational impact identified so far.

Infosecurity Magazine · 14d agoRansomware

Stronger Security Drives Ransomware Groups to Recruit From Within

Researchers report ransomware groups increasingly recruiting insiders at target companies to bypass stronger security, with insider-assisted attacks costing victims millions.

Security researchers have observed an uptick in insider-assisted ransomware attacks as organizations strengthen their defenses. Ransomware groups are reportedly recruiting from within target companies, and malicious insiders also enable other costly threats. No specific victims or campaigns are named in the report.

Dark Reading · 15d agoRansomware

GentleKiller targets more than 400 security processes across 48 products

ESET details the Gentlemen ransomware gang's in-house GentleKiller EDR-killer framework targeting over 400 security processes across 48 products, supplied to affiliates.

ESET analyzed the Gentlemen ransomware gang's in-house GentleKiller EDR-killer framework, confirmed through an internal data leak from May 2026. The framework has at least eight variants impersonating legitimate security products and abusing vulnerable or malicious kernel drivers, targeting more than 400 process names across 48 security products. Gentlemen emerged in late 2025, became one of the five most active ransomware gangs in Q1 2026, offers affiliates a 90% ransom share, and practices double extortion using Go-based and C-based ESXi encryptors. The suite also reuses outside tools including HexKiller, ThrottleBlood, and HavocKiller, unified by a shared evasion layer that mimics well-known security vendors.

Help Net Security · 24d agoRansomware in the wild

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