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7 stories in the last 30d

⚡ Weekly Recap: VMware Exploits, Windows 0-Day, MCP Attacks, Browser Hijacks and More

Weekly recap: suspected China-nexus APT exploited VMware vCenter CVE-2026-59310, Lazarus used Windows zero-day CVE-2026-68820, and macOS flaw dropped Monero miners.

The week's top stories included a suspected China-nexus APT exploiting VMware vCenter CVE-2026-59310 (CVSS 9.8), a directory-traversal flaw enabling arbitrary code execution, with backdoors, reverse SSH and Babuk-derived ransomware deployed, per QUIRSO. NCSC-NL reported active exploitation of macOS Screen Sharing flaw CVE-2026-65400 (CVSS 9.8) to install Monero miners on systems with port 5900 exposed. Lazarus Group exploited Windows zero-day CVE-2026-68820 (CVSS 7.0) in Operation Dream Job, delivering ForestTiger and Troy backdoors to defense and aerospace targets. GeoServer patched a critical SQL injection flaw exploited within hours of disclosure, and Jamf analyzed the new Amnesia Stealer for macOS with live browser control.

Impersonating IT support: how threat actors turn a remote session into enterprise-wide access

Microsoft details Teams IT-support impersonation campaigns deploying Node.js implants, AD reconnaissance, and WinRM lateral movement toward domain controllers.

Microsoft Threat Intelligence describes a human-operated campaign where attackers impersonate IT/helpdesk staff via Microsoft Teams external collaboration, talk users into granting remote sessions, and use RMM tools for interactive access. During the session they run PowerShell to silently install a malicious MSI that stages a portable Node.js runtime and obfuscated JavaScript implant for C2, executing follow-on payloads via rundll32. Operators then perform host and Active Directory reconnaissance, capture desktop screenshots, and pivot via WinRM on port 5985 to domain controllers and certificate authorities. The hands-on-keyboard chain, which can precede data theft and ransomware, blends into normal operations by relying on Teams, Quick Assist, msiexec, and Node.js; Microsoft shares hunting and mitigation guidance.

Microsoft Security Blog · 13d agoThreat actor in the wild

Threat Assessment: Egregor Ransomware

Unit 42 assesses Egregor ransomware, a Sekhmet variant likely run by former Maze affiliates using Qakbot, IcedID, and Ursnif for initial access.

Since September 2020, Unit 42 observed Egregor ransomware attacks across the U.S., Europe, Asia-Pacific, and Latin America, coinciding with the Maze team's shutdown announcement. Egregor, a variant of the Sekhmet family, uses commodity malware such as Qakbot, IcedID, and Ursnif for initial access, followed by scripts that modify firewalls, enable RDP, and deploy Cobalt Strike for reconnaissance and exfiltration. A PowerShell script uninstalls the McAfee agent and downloads the Egregor DLL via BITS, executed with the -passegregor10 key. Victims face a three-day ransom deadline before exfiltrated data is published on the Egregor Hall of Shame leak site.

Palo Alto Unit 42 · 29d agoRansomware in the wild

Threat Brief: Maze Ransomware

Unit 42 issued a threat brief on Maze ransomware, noting an uptick across industries and exploitation of Pulse VPN and IE flaws for initial access.

Palo Alto Networks detected an uptick in Maze ransomware samples across finance, healthcare, government, and other sectors. Maze, a variant of ChaCha ransomware first seen in May 2019, is distributed via weaponized Word/Excel attachments and the Spelevo exploit kit leveraging CVE-2018-15982 and CVE-2018-4878, and has used CVE-2019-11510 (Pulse VPN) and CVE-2018-8174 (Internet Explorer). Operators establish a foothold, escalate privileges, move laterally, and exfiltrate files before encryption for extortion leverage.

Palo Alto Unit 42 · 29d agoRansomware in the wildCVE-2018-15982CVE-2018-4878CVE-2019-11510+1 CVEs

ThreatsDay: CEO Phishing Kits, 5K Dropbox Account Hacks, OAuth Traps + 17 More Stories

Microsoft warns of Teams IT-impersonation intrusions deploying Node.js implants; Spring Ring vishing hit 150+ employees across 10 companies; The Gentlemen ransomware claims 683 victims.

Microsoft warned of a human-operated campaign abusing Teams external collaboration to impersonate IT help desk staff, deploy malicious MSI packages staging Node.js runtimes and obfuscated JavaScript implants, then pivot to domain controllers over WinRM. Unit 42 documented the Spring Ring vishing operation targeting over 150 employees across at least 10 companies using 26 attacker identities, including an NTLM relay variant against domain controllers. Sophos reported The Gentlemen ransomware (Gold Sherwood) reached 683 total victims by end of July 2026, adding 169 in July, with a playbook using BYOVD-based EDR killers and backup tampering. Group-IB found the Outsider phishing-as-a-service platform created 700+ new phishing pages within a month despite law enforcement takedowns.

The Hacker News · 12d agoThreat actor in the wild1

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.

Palo Alto Unit 42 · 29d agoRansomware in the wild

H1 2026 Malware Vulnerability Trends

Recorded Future's H1 2026 report finds 215 actively exploited CVEs, RAT dominance, NFC payment fraud, and AI-augmented but not autonomous tradecraft.

Recorded Future's Insikt Group identified 215 actively exploited CVEs in H1 2026, up 34% from 161 in H1 2025, with the most impactful flaws combining network reachability, no authentication, and code execution. AsyncRAT was the top malware family, with AsyncRAT, Cobalt Strike, XWorm, Stealc, and REMCOS remaining top-ten staples; Android NFC malware like NFCShare and NGate enabled payment card theft and ATM cash-outs. AI-enabled attacks remained additive to established tradecraft, concentrated in Levels 1-3 of Recorded Future's AIM3 maturity model, with AI-assisted vulnerability research (e.g., Claude Mythos fixing 271 Firefox bugs in Firefox 150) inflating NVD disclosure volumes 43% above the prior six-month average. The report urges defenders to prioritize remotely exploitable RCE flaws, behavioral detection, developer credential security, and third-party oversight.

Recorded Future · 13d agoThreat actor in the wild1