Chinese espionage groups swarm to exploit triple-link chain of zero-days
At least four China-aligned espionage groups chained three zero-days in Chromium browsers and Windows ALPC for espionage since late August.
Proofpoint observed at least four state-aligned threat groups, starting with TA412/Violet Typhoon/APT31 on August 28, chaining three zero-days in the 'BlueMoon' exploit chain targeting Chrome, Chromium-based browsers and Microsoft Windows. The chain includes RCE flaws in Chromium's JavaScript engine (CVE-2026-85046, CVE-2026-87491) and a Windows Advanced Local Procedure Call privilege-escalation zero-day (CVE-2026-85880), enabling sandbox code execution, sandbox escape and system privileges. APT31 delivered the chain via phishing links to NGOs, mining and commodity trading firms in the US, installing a browser extension disguised as Google Gemini to surveil activity and steal credentials. Other groups (UNK_LateNight, UNK_DoubleCheck, UNK_QuietRacket) targeted US aerospace, Vietnamese manufacturing, and Indonesian and Singaporean organizations; fewer than 20 victims were directly observed but the true count is likely higher.
Four Nation-State Actors Used the Same Chrome Zero-Day Exploit Kit Within 12 Days
Proofpoint reports four nation-state actors, mostly China-nexus, adopted the BlueMoon Chrome and Windows zero-day exploit kit within 12 days, targeting US organizations.
Proofpoint tracked an exploit kit dubbed BlueMoon that chains CVE-2026-85046, a Chrome V8 type-confusion bug, with an unnamed V8 sandbox escape and CVE-2026-85880, a Windows kernel privilege escalation using ALPC and the Windows Notification Facility. The first observed use was by China-nexus TA412 (APT31, Violet Typhoon, JungleBamboo) on August 28, 2026 against US NGOs, mining companies, and commodity trading firms, followed by UNK_LateNight targeting US aerospace and defense companies on September 2. Both V8 bugs were patch-gap zero-days: the fix was committed to Chromium on August 7 but reached stable Chrome on September 3, enabling rapid weaponization from public patches. TA412's post-exploitation payload, GemStone, is a malicious browser extension posing as an AI-powered Google Gemini companion that captures keystrokes, cookies, screenshots, and browsing history via a Cloudflare Worker C2.
Novel Blue Moon kit targeting Chrome and Windows reflects new reality of AI-driven exploits
Proofpoint reports the BlueMoon exploit kit, chaining two Chrome V8 zero-days and a Windows ALPC bug, being shared across China-linked espionage groups.
Proofpoint identified a new exploit kit, BlueMoon, first observed on August 28 and used by TA412 (APT31/Violet Typhoon) against US NGOs, mining firms, and commodity trading companies. The kit chains a V8 type confusion RCE (CVE-2026-85046), a V8 sandbox escape, and a Windows Advanced Local Procedure Call privilege escalation (CVE-2026-85880), both patched flaws having been exploited in the wild. At least four espionage groups, most with suspected China nexus including UNK_LateNight, adopted the kit within days, targeting US aerospace firms with defense-sector lures. Fewer than 20 organizations were observed targeted, and researchers believe AI-assisted exploit development against upstream Chromium patches enabled the kit's rapid creation and sharing.
Multiple Chinese hacking groups seen using identical Chrome zero-day exploit
Four China-linked espionage groups share identical BlueMoon Chrome zero-day exploit kit targeting US defense contractors and Asian government agencies.
Proofpoint identified at least four Chinese-aligned espionage groups (TA412/RedBravo, UNK_LateNight, UNK_DoubleCheck, UNK_QuietRacket) using an identical Chrome zero-day exploit kit dubbed BlueMoon in late August through this week. Targets include US defense contractors, NGOs, mining companies, and Southeast Asian government agencies. The exploit chains a Chromium patch-gap vulnerability with a Windows flaw, delivering malware such as ShadowPad and a fake Gemini browser extension backdoor, with possible AI-assisted exploit development.