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.