Chaotic Eclipse Releases GenDigital Avast Antivirus ZeroDay PrettyPrague
Researcher Chaotic Eclipse released PrettyPrague, a PoC zero-day privilege escalation exploit against fully patched GenDigital Avast Antivirus.
Security researcher Chaotic Eclipse (also known as INFINITE NIGHTMARE or MSNightmare) published a PoC named PrettyPrague exploiting a zero-day privilege escalation flaw in Avast Antivirus. The PoC abuses a flaw in the Avast Sandbox to dump the Windows SAM database and spawn a SYSTEM-level shell, reportedly working on fully patched Avast and patched Windows 11 25H2. The researcher believes the flaw may also affect other GenDigital products such as AVG and Norton. It follows his recent HardBreacher PoC for a Kaspersky Endpoint Security privilege escalation flaw.
AI helps scammers build convincing antivirus renewal pages
Malwarebytes found scammers using AI to build polished fake antivirus renewal pages impersonating Avast, harvesting names, emails and phone numbers for follow-up fraud calls.
Malwarebytes analyzed a fake Avast renewal site targeting Belgian users in French, claiming a €129.99 Avast Premium Security renewal and collecting name, email address and Belgian mobile number through a cancellation form. Leftover code comments written in polite French and other stylistic clues suggest the page was generated with AI assistance, and the form was never connected to send data anywhere. The scam typically progresses to phone calls pressuring victims to install remote access software, and AI substantially lowers the barrier for producing polished, localized scam pages at scale.
Threat Assessment: Ryuk Ransomware
Unit 42 assesses Ryuk ransomware amid a CISA/FBI/HHS alert on threats to U.S. healthcare, including the UHS attack that disrupted hospital operations.
A joint CISA, FBI, and HHS alert on October 28, 2020 warned of an imminent threat to U.S. healthcare from operators deploying Trickbot and Ryuk ransomware. Universal Health Services reported a Ryuk attack that disrupted all U.S. UHS sites for weeks, with similar incidents at hospitals in Oregon and New York. Ryuk typically arrives after Trickbot or BazaLoader infections delivered via malicious email, and operators enumerate networks with PowerShell and WMI before encryption. The Trickbot Anchor_DNS module performs DNS tunneling for C2, using connectivity checks to benign domains like ipinfo.io and checkip.amazonaws.com.