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Researchers Uncover 10,000+ Malware Loaders Behind YouTube and SEO Poisoning Campaign

Unit 42 uncovers CL-CRI-1171, a two-year pay-per-install campaign distributing 10,000+ OfferLoader samples via YouTube and SEO poisoning.

Palo Alto Networks Unit 42 tracked a campaign as CL-CRI-1171, an infection-as-a-service platform operating for at least two years. It used 11 YouTube gaming channels with hundreds of thousands of subscribers and SEO-poisoned download pages for trojanized WinDirStat and Bluetooth driver installers to distribute OfferLoader, a disposable loader embedded in Inno Setup installers. Payloads delivered included Insomnia RAT (Node.js and Python backdoors), ARKTunnel (a WebSocket-based RAT using LSB steganography), and Docro Hijacker (Chrome browser hijacker), with later infections delivering GCleaner and Socks5Systemz. Over 200 rotating domains across .xyz, .cfd, .space, and .info TLDs were used, with gating filters that served broken links or decoy pages to scanners and researchers.

GBHackers · 5d agoMalware in the wild2

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