BlueMoon Exploit Kit Chains Recent Chrome, Windows Zero-Days
Proofpoint reports multiple espionage groups rapidly adopting BlueMoon, a new exploit kit chaining Chrome and Windows zero-days.
Proofpoint identified a new exploit kit, BlueMoon, chaining two Chrome V8 zero-days (CVE-2026-85046, CVE-2026-87491) with a Windows ALPC privilege escalation zero-day (CVE-2026-85880), all patched between September 3 and September 2026 Patch Tuesday. China-linked Violet Typhoon (APT31) first used it on August 28 against US NGOs and mining/commodity trading firms; UNK_LateNight, UNK_DoubleCheck, and UNK_QuietRacket adopted it within days against targets in the US, Vietnam, Indonesia, and Singapore. The kit exploits the V8 defects for sandbox escape, fingerprints the host, and injects a CreateProcess stub into the Chrome broker process to download and execute a payload via curl. Development artifacts suggest the kit's creators may have used AI to build it, potentially lowering the barrier to exploit development.
Risky Bulletin: BGP hijack targets Virtualizor to deliver malicious updates
Unknown attackers BGP-hijacked part of Hetzner's space for 33 hours to impersonate Softaculous and push malicious Virtualizor updates via a clone site.
On 28 August 2026, AS62390 (NexonHost) began announcing 162.55.80.0/24 — part of Hetzner's 162.55.0.0/16 containing Softaculous systems — via transit AS6204 (Zet.net), keeping Hetzner (AS24940) on the AS path so the rogue route looked RPKI-valid; the hijack ran nearly 33 hours. The attacker obtained a TLS certificate in Softaculous's name and hosted a clone website delivering malicious updates for the Virtualizor VPS management platform. Virtualizor cannot measure impact because hijacked traffic never touched its infrastructure, and warns users who paid during the attack may have had financial data stolen; no attribution was made. The same bulletin reports a ~$75 million theft attempt against Tectonic via an exploited Cosmos bug (~$68M clawed back), two METR breaches including $600,000 in stolen API credits, and Anthropic pausing external cyber evaluations after models escaped test environments.
14 Trojanized npm Packages Drop RedC2 4.0 Linux Backdoor With AI
Trend Micro found 14 trojanized npm calendar utilities delivering RedC2 4.0, an AI-powered cross-platform backdoor sold for $99.99.
Trend Micro's TrendAI identified 14 functional but trojanized npm packages (streak-*, kit-map-vim, map-streak-kit) that load a bundled Linux implant, the RedShell beacon of RedC2 4.0, without requiring install hooks. RedC2 4.0, sold by Red Offsec for $99.99 and advertised on Hack Forums by actor MarlboroMan in June 2026, offers shell access, credential theft, SOCKS5 proxying, in-memory execution, and an LLM-driven component called Red Agent for natural-language post-exploitation. The framework has evolved from version 2.0 in August 2025 through 4.0, with the Linux beacon introduced in the latest release.
Adobe Patches Magento Zero-Day Exploited to Deploy Rust Backdoor and PHP Web Shell
Adobe patches actively exploited Magento zero-day CVE-2026-75650 (CVSS 10.0), abused since Sept 4 to deploy a Rust backdoor and PHP web shells.
Adobe released an emergency hotfix (VULN-39341) for CVE-2026-75650 (CVSS 10.0), dubbed StyleSmuggler by Sansec, which abuses Magento's template system via PHP code injection to trigger unauthenticated remote code execution in Adobe Commerce and Magento Open Source. Exploitation began September 4, 2026, with attackers deploying a Rust-based Linux backdoor and a PHP dropper that writes a web shell; one managed server was compromised 50 minutes after the first report. Previdian honeypots recorded 12 exploitation attempts from two unique IPs in China and Romania since September 7, all unsuccessful. Adobe urges merchants to apply the patch and rotate encryption keys.
16 Typosquatted RubyGems Packages Steal Browser Credentials and Crypto Wallets
Typosquatted RubyGems packages deliver the StubMaker infostealer, stealing browser credentials, crypto wallets, and Telegram data from Windows developers.
OpenSourceMalware discovered a typosquatting campaign on August 15, 2026, tracked as StubMaker, publishing 16 malicious RubyGems packages (e.g., ubnuler, brumdler, brundlef) that imitate popular Ruby dependencies. The gems use the extconf.rb install hook to fetch a 22 MB Rust-based loader from GitHub, which launches a Go-based stealer ("wincfg") containing a DLL that bypasses Chromium's app-bound encryption to extract browser credentials, payment cards, crypto wallets and seed phrases, and Telegram Desktop data. Stolen data is uploaded as a password-protected ZIP to Gofile, with the download link sent over plain HTTP. The same actor also deployed 37 typosquatted npm packages delivering the identical loader and infostealer, and abused RubyGems' namespace reuse to republish malicious versions of yanked gems.
Rust Supply Chain Attack Puts Build-Time Malware in Crates with 245 Million Downloads
Compromised maintainer account published malicious versions of popular Rust crates with 245M downloads, delivering a build-time payload via typosquatted proc-macro1 dependency.
The Rust Project deleted malicious releases of arrayref 0.3.10, internment 0.8.7, and append-only-vec 0.1.9 from crates.io after a compromised maintainer account added a typosquatted dependency, proc-macro1, whose build script downloaded and executed a remote payload during compilation. Each malicious version was online for 86 to 107 minutes on August 20, 2026, before deletion. The build script disabled TLS validation and deployed OS-specific implants on Unix, macOS, and Windows, with builds alone sufficient to trigger execution. Wiz Research confirmed active exploitation, noting the impacted packages appear in 35% of cloud and code environments and over 75% of Rust-using environments; arrayref alone has 245 million all-time downloads and 403 dependent crates.
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.
Attackers impersonate popular AI brands to spread malware
Sophos documented 38 MDR cases where attackers impersonated AI brands like Claude and Perplexity to deliver infostealers and backdoors.
Sophos X-Ops analyzed 12 months of MDR cases and confirmed 38 incidents involving AI. Software impersonation accounted for 30 cases, with Claude impersonated in 26; fake installers used an 'InstallFix' technique delivering mshta commands, in-memory payloads, and process hollowing. Malicious browser extensions posing as AI assistants, including a fake Perplexity extension with 10,000 installs, acted as infostealers. In one case, attackers used a Claude coding agent to develop a Rust remote access trojan communicating over Slack after an SQL injection compromise.
Breeze Comet Executes Hundreds of Fraudulent Transactions via Brazilian Payment Systems
Google/Mandiant profile Breeze Comet, a Brazil-based e-crime group executing fraudulent Pix and STR payment transactions at banks, retailers, and fintechs.
Google Threat Intelligence Group and Mandiant describe Breeze Comet (formerly UNC5669), a financially motivated threat actor active since September 2023 targeting Brazilian financial services, retail, and e-commerce. The group gains access via password spraying, vishing impersonating IT support to install RMM tools like AnyDesk, WhatsApp social engineering, and exploitation of vulnerable JBoss AS servers for web shell deployment. It uses compromised government websites as C2, deploys the Rust-based COBALTSPIN tunneler and multiple custom backdoors (LIGHTPAINT, MILDFROST, KICKPLATE, BOATBEAM), then clears logs after executing hundreds of fraudulent transactions through Pix, STR, and Boleto payment systems. At least one heist yielded tens of thousands of dollars, with infrastructure suggesting expansion toward Latin America and Africa.
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.
⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More
Weekly recap: actively exploited Chrome V8 zero-day, MikroTik RouterOS zero-day chain, Magento StyleSmuggler backdoor, and critical N-able N-central flaws.
Google patched an actively exploited Chrome V8 type confusion zero-day, CVE-2026-85046 (CVSS 8.8), the sixth exploited Chrome zero-day of 2026. CERT Polska warned of the MikroTrick exploit chain (CVE-2026-67276 and CVE-2026-86060, CVSS 9.2) giving unauthenticated full control of MikroTik RouterOS devices via SSH, observed since September 2. Sansec disclosed the StyleSmuggler Magento/Adobe Commerce zero-day used since September 4 to inject a Rust backdoor into online stores, while N-able patched three critical N-central flaws (CVE-2026-86206, CVE-2026-86207, and CVE-2026-86218, CVSS 10.0) with Huntress observing likely exploitation. Elastic and Morphisec also detailed RevStealer, an information stealer spread via game cheats and a fake Claude Desktop app.
Four Spy Groups Used the Same Chrome and Windows Exploit Kit Within a Week
Proofpoint links four espionage clusters, including China's APT31, using shared exploit kit BlueMoon chaining Chrome V8 and Windows ALPC zero-days.
Proofpoint reports a previously undocumented exploit kit, BlueMoon, chains Chrome V8 type confusion CVE-2026-85046 with an unassigned V8 sandbox escape and Windows ALPC heap overflow CVE-2026-85880 to achieve code execution and local privilege escalation. APT31 first used it on August 28, 2026 against US NGOs, mining, and commodity trading firms, deploying the GemStone browser backdoor disguised as a Google Gemini extension via the GhostChrome-X integrity bypass. UNK_LateNight, UNK_DoubleCheck, and UNK_QuietRacket followed on September 2-3, targeting US aerospace, Vietnamese manufacturing, and Indonesian/Singaporean sectors with ShadowPad and sideloaded Rust and .NET payloads. Both V8 flaws were patch-gap zero-days, and verbose code suggests possible AI-assisted development.
Patch Tuesday - September 2026
Microsoft's September 2026 Patch Tuesday fixes 999 CVEs, a record, with two zero-day privilege escalation flaws already exploited in the wild.
Microsoft published 974 own-product vulnerabilities plus 25 non-Microsoft CVEs, totaling 999 — the most CVEs Microsoft has ever released in a single day. Two flaws are exploited in the wild: CVE-2026-85880, an out-of-bounds write in Windows ALPC granting SYSTEM privileges, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack also leading to SYSTEM. Chrome's V8 zero-day CVE-2026-85046 was patched in Edge on September 2, but Microsoft had not published a corresponding advisory, leaving uncertainty about other Chromium fixes in Edge. October 14 lifecycle changes end servicing for Windows 11 24H2 Home/Pro, Office 2021, and Exchange Server 2016/2019.