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Three Threat Groups Target Russian Enterprises With Backdoors, Ransomware, and Wipers

Kaspersky details NightEagle, Hacking Cat, and Toy Ghouls targeting Russian enterprises with Exchange backdoors, Gorilla RAT, and destructive Monkey ransomware.

Kaspersky reports three threat clusters targeting Russian enterprises: NightEagle (APT-Q-95), the pro-Ukrainian hacktivist group Hacking Cat, and Toy Ghouls. NightEagle uses compromised VPN credentials and the GhostContainer modular backdoor to fully compromise Microsoft Exchange servers, chaining CVE-2020-0688 exploitation, BlueKeep (CVE-2019-0708), Active Directory vulnerabilities, and DCSync to seize domain controllers. Hacking Cat exploits Exchange flaws including CVE-2021-26855 and CVE-2026-42897 to deliver the Gorilla RAT and multiple Monkey ransomware variants written in Rust, .NET, C++, and Golang targeting Windows, Linux, and VMware ESXi, with some variants acting as wipers that never store the encryption key.

China-Linked Hackers Exploit Chrome-Windows Zero-Day Chain to Deploy GRIMWEDGE

Volexity attributes spear-phishing campaign exploiting Chrome-Windows zero-day chain to Chinese actors UTA0560 and APT31 deploying GRIMWEDGE and LONGTALE.

Volexity attributes a September 1, 2026 spear-phishing campaign targeting NGOs to China-linked UTA0560, which abused a reflected XSS flaw on a US university website to trigger a three-part exploit chain (CVE-2026-85046, CVE-2026-87491, CVE-2026-85880) escaping the Chrome V8 and browser sandboxes to deploy the GRIMWEDGE JavaScript backdoor with reconnaissance, file management, and command execution capabilities. The same chain was used near-simultaneously by JungleBamboo (APT31) to deploy SUPERSTOMP, installing the LONGTALE/GemStone credential-stealing Chrome extension masquerading as Google Gemini. The Chrome flaws were patched in Chromium but not yet in stable Chrome, creating an unusual patch-gap zero-day window attackers raced to exploit.

The Hacker Newsupdated · 10h agofirst · 1d agoThreat actor in the wild 14 sourcesCVE-2026-85046CVE-2026-87491CVE-2026-858801· 1 read

Pro-Ukraine Hacking Cat group deploying new malware against Russian targets

Kaspersky links pro-Ukraine hacktivist group Hacking Cat to Gorilla RAT and Monkey Ransomware in destructive attacks on Russian targets.

Kaspersky reports that pro-Ukraine group Hacking Cat, active since February 2024, has shifted from defacements to destructive encryption attacks, using a previously undocumented Gorilla RAT remote-access tool and Monkey Ransomware, which appends the .monkey extension to files. Initial access in some attacks came from exploited Microsoft Exchange vulnerabilities, and rapid multi-language malware variants suggest possible generative AI assistance. Shared tools like Nemo Wiper across groups including Ukrainian Cyber Alliance complicate attribution, and targets include Rosatom contractor and heating provider Donbassteploenergo.

The Record · 2d agoThreat actor in the wild

Microsoft’s Patching

Microsoft's September Patch Tuesday fixes a record 972 vulnerabilities, 112 rated critical, amid AI-accelerated vulnerability discovery.

Microsoft's September 2026 Patch Tuesday patches a record ~972 vulnerabilities, 112 rated critical, following records of 570 two months ago and ~620 last month. Schneier attributes the surge to AI-powered vulnerability finding, citing an open letter from OpenAI, Anthropic, AWS, Google, Microsoft and roughly 100 organizations warning of an AI-enabled attack tsunami. He predicts AIs will reverse-engineer exploits from patches, weaponizing flaws immediately upon release and shrinking the patch window to 'immediately.'

Schneier on Security · 2d agoVulnerability1

Anthropic Says Russian Hackers Used Claude AI to Automate Malware Evasion

Anthropic disrupted Midnight Blizzard campaigns where AI agents automatically rebuilt malware to evade detection, targeting 20+ government and defense organizations.

Anthropic's threat intelligence report documents the Russian state-nexus actor Midnight Blizzard using Claude to automatically monitor, modify, and redeploy malware until it evaded security products. The campaign hit more than 20 organizations, including Ukrainian and European government ministries, defense bodies, embassies, and think tanks, with mailbox theft from two drone component manufacturers and compromise of hotel guest Wi-Fi via DNS hijacking. The report also describes financially motivated groups GTG-50020 and GTG-50021 targeting AI credentials, including a prompt-injection attack on an automated evaluation sandbox that yielded production API keys and attempts to reach a pre-release Claude model across roughly 30 AI companies.

SecurityWeekupdated · 13h agofirst · 5d agoThreat actor in the wild 18 sources4