⚡ Weekly Recap: VMware Exploits, Windows 0-Day, MCP Attacks, Browser Hijacks and More
Weekly recap: suspected China-nexus APT exploited VMware vCenter CVE-2026-59310, Lazarus used Windows zero-day CVE-2026-68820, and macOS flaw dropped Monero miners.
The week's top stories included a suspected China-nexus APT exploiting VMware vCenter CVE-2026-59310 (CVSS 9.8), a directory-traversal flaw enabling arbitrary code execution, with backdoors, reverse SSH and Babuk-derived ransomware deployed, per QUIRSO. NCSC-NL reported active exploitation of macOS Screen Sharing flaw CVE-2026-65400 (CVSS 9.8) to install Monero miners on systems with port 5900 exposed. Lazarus Group exploited Windows zero-day CVE-2026-68820 (CVSS 7.0) in Operation Dream Job, delivering ForestTiger and Troy backdoors to defense and aerospace targets. GeoServer patched a critical SQL injection flaw exploited within hours of disclosure, and Jamf analyzed the new Amnesia Stealer for macOS with live browser control.
Decline in Rig Exploit Kit
Rig exploit kit activity dropped roughly 75% after the pseudo-Darkleech and EITest campaigns stopped using EKs, reflecting an overall decline in exploit kit activity.
Rig EK activity fell sharply in 2017: the pseudo-Darkleech campaign disappeared at the end of March, cutting Rig traffic about 50%, and the EITest campaign switched to tech support scams in late April, cutting another 50% in May. Broader causes include a shrinking browser target base, no major EK zero-day in over a year, and community takedowns of domain shadowing infrastructure. Criminals are shifting to malspam, social engineering schemes like fake HoeflerText notifications, and tech support scams.
Microsoft breaks Patch Tuesday record with 974-CVE deluge
Microsoft's record 974-CVE Patch Tuesday ships two exploited Windows zero-days, while Adobe's StyleSmuggler zero-day (CVE-2026-75650) gives unauthenticated RCE in Magento.
Microsoft's September Patch Tuesday addresses 974 CVEs, including two zero-days already under exploitation: CVE-2026-85880, a Windows ALPC privilege escalation leading to SYSTEM via sandbox escape, and CVE-2026-81963, a Windows Update Stack privilege escalation. Adobe patched 172 CVEs, including the max-severity StyleSmuggler zero-day CVE-2026-75650 in Magento and Adobe Commerce, which Sansec reports is being exploited since September 4 to inject PHP into templates and install a C2-connected backdoor. CISA added CVE-2026-85880, CVE-2026-81963, and CVE-2026-75650 to its Known Exploited Vulnerabilities Catalog with patch deadlines of September 22 and September 11. The piece also notes Google-patched Chrome V8 zero-day CVE-2026-85046 lacks a Microsoft advisory for Edge, and flags nine Exchange Server flaws including remote unauthenticated RCE CVE-2026-55007.
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.
CISA Warns of Chromium Type Confusion 0-Day Vulnerability Actively Exploited in Attacks
CISA added the actively exploited Chromium V8 type confusion zero-day CVE-2026-85046 to its KEV catalog, urging patching of Chrome, Edge, and Opera.
CISA added CVE-2026-85046, a V8 type confusion flaw (CWE-843) in Chromium-based browsers, to its Known Exploited Vulnerabilities catalog. A remote attacker can trigger arbitrary code execution inside the browser sandbox via a specially crafted HTML page. Google Chrome is directly affected, and Microsoft Edge, Opera, and other Chromium-based browsers may also be impacted depending on their V8 version. Google has released a Stable channel Chrome update, and CISA directs mitigations under Binding Operational Directive 26-04.
Rogue ScreenConnect Installations Across Unrelated Hosts Suggest Worm-Like Activity
Huntress observed rogue ScreenConnect deployments with worm-like VBScript propagation across unrelated organizations, prompting a ConnectWise advisory on file transfer behavior.
Huntress identified multiple incidents in late August 2026 where social engineering led to rogue ScreenConnect remote access clients deployed on victim machines, which then spawned wscript.exe to run four VBScript payloads (1.vbs through 4.vbs) for profiling, telemetry collection, and persistence via a WindowsServiceHost Run key. Modified ScreenConnect clients propagated the VBScript chain to connected endpoints, creating worm-like spread. ConnectWise published an advisory on September 3, 2026, confirming an issue affecting file transfer behavior in both cloud and on-premises ScreenConnect deployments, with a CVE and fix expected within the week; partners were advised to review and disable TransferFiles permissions in the interim.
Google Pixel phones pwned in zero-click attacks
CISA added actively exploited zero-click Pixel modem flaw CVE-2026-58704 to its KEV catalog, giving federal agencies three days to patch.
Google disclosed CVE-2026-58704, a high-severity improper authorization flaw in Pixel phones' cellular modems that bypasses permission checks and escalates privileges with no user interaction, noting limited, targeted exploitation. CISA added it to the Known Exploited Vulnerabilities Catalog with a September 19 deadline for federal agencies. Such zero-click modem bugs are a frequent vector for commercial spyware. The Register also notes two recently KEV-listed Chromium V8 flaws, CVE-2026-85046 and CVE-2026-87491, which Proofpoint says four espionage groups chained in intrusions.
Chrome V8 Zero-Day Exploited in the Wild Enables Code Execution Inside Sandbox
Google patches actively exploited Chrome V8 zero-day CVE-2026-87491, an out-of-bounds write enabling sandboxed code execution via crafted HTML pages.
Google released Chrome 153.0.8010.36/.37 fixing 230 vulnerabilities, including CVE-2026-87491, an out-of-bounds write in the V8 engine that allowed remote code execution inside the sandbox via a crafted HTML page and is confirmed to be exploited in the wild. The flaw was reported on August 6, 2026 by Jihyeon Jeong of Compsec Lab, Seoul National University, who received a $2,500 bug bounty. This is the seventh actively exploited Chrome zero-day of 2026. The update also fixes five critical flaws in WebGL and Cast, plus a high WebPackaging use-after-free (CVE-2026-87639) credited to OpenAI Codex Security.
Google Releases Chrome Update to Patch Actively Exploited V8 Zero-Day
Google patches actively exploited Chrome V8 zero-day CVE-2026-85046 (CVSS 8.8); CISA adds it to KEV with a September 18 deadline.
Google fixed 12 Chrome vulnerabilities, including CVE-2026-85046, a high-severity (CVSS 8.8) type confusion bug in the V8 JavaScript and WebAssembly engine. The flaw, reported by researcher Salvatore Gulizia on August 4, 2026, allows remote arbitrary code execution inside the browser sandbox via a crafted HTML page. Google confirmed the exploit exists in the wild, and CISA added the CVE to its KEV catalog, requiring Federal Civilian Executive Branch agencies to patch by September 18, 2026. This is the sixth actively exploited Chrome zero-day patched in 2026.