One Exploit Chain, Two Espionage Campaigns: Chrome and Windows Under Fire
Two China-linked APT groups reused identical Chrome/Windows zero-day chain against NGOs, deploying GRIMWIDGE backdoor and LONGTALE credential-stealing extension.
Volexity reports that China-linked actors UTA0560 and JungleBamboo (APT31/TA412) ran byte-identical Chrome/Windows exploit chains against NGOs starting September 1, 2026, combining Chrome type confusion CVE-2026-85046, WebAssembly sandbox escape CVE-2026-87491, and Windows kernel flaw CVE-2026-85880. The Chrome bug was fixed in Chromium source but not yet shipped to Chrome users, making it an effective zero-day with an unusual patch gap. UTA0560 delivered the in-memory GRIMWEDGE JScript backdoor, while JungleBamboo deployed the SUPERSTOMP loader installing LONGTALE, a malicious Chrome extension disguised as Google Gemini that steals cookies, session tokens, and keystrokes. Volexity assesses with low confidence the exploit chain was sold or shared among different Chinese end-users.
Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories
Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.
Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.
Hackers Chain Chrome and Windows Zero-Days in New BlueMoon Exploit Kit Attacks
Multiple espionage actors, mostly China-nexus, are chaining Chrome V8 and Windows kernel zero-days (CVE-2026-85046, CVE-2026-85880) via the BlueMoon exploit kit against government and defense targets.
Proofpoint identified a new exploit kit dubbed BlueMoon chaining a Chromium V8 type-confusion RCE (CVE-2026-85046), a V8 sandbox escape, and a Windows kernel LPE (CVE-2026-85880). At least four distinct threat clusters, most with suspected China nexus, adopted the kit within days starting with TA412 (Violet Typhoon/APT31) on August 28, 2026. Both Chrome-side flaws were patch-gap zero-days with roughly a four-week exploitation window; the Windows LPE only works on Windows 10 and Server 2019/2022. TA412 used spearphishing posing as university interns to deliver the GemStone browser backdoor disguised as a Google Gemini extension; other clusters delivered ShadowPad via DLL sideloading and a Rust loader against targets in aerospace, government, and finance.
Unit 42 Researchers Discover Multiple Espionage Operations Targeting Southeast Asian Government
Unit 42 attributes three espionage clusters targeting a Southeast Asian government to Stately Taurus, Alloy Taurus, and Gelsemium APTs.
Unit 42 investigated espionage attacks starting in late 2022 against multiple governmental entities in a Southeast Asian country, including critical infrastructure, public healthcare, financial administrators, and ministries. Analysis revealed three distinct clusters: CL-STA-0044 attributed to Stately Taurus (Mustang Panda), CL-STA-0045 to Alloy Taurus (GALLIUM), and CL-STA-0046 to Gelsemium. The first cluster used a ToneShell backdoor variant, ShadowPad, China Chopper web shells, Impacket, and credential dumping tools across roughly Q1 2021 to Q3 2023. All three operated with distinct tools, infrastructure, and long-term surveillance tradecraft consistent with APTs.