Microsoft Shatters Patch Tuesday Record With 974 CVE Fixes in September 2026
Microsoft's September 2026 Patch Tuesday fixes a record 974 CVEs, including two actively exploited Windows zero-days, CVE-2026-85880 and CVE-2026-81963.
Microsoft fixed a record 974 CVEs in its September 2026 Patch Tuesday, surpassing the previous record of 570 in July 2026, with Windows affected by 723 flaws and Office by 111, including 119 critical vulnerabilities. Two zero-days are actively exploited: CVE-2026-85880, a 7.8 heap-based buffer overflow in Windows ALPC allowing AppContainer privilege escalation, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack enabling local privilege escalation. Microsoft attributed the update surge partly to agentic AI tools used to discover zero-day vulnerabilities, and researchers highlighted critical RCE flaws in Windows DNS, DHCP and Deployment Services as priorities.
Attackers Exploit Critical Cisco FMC Flaw to deploy Qilin ransomware
Three threat groups, including Qilin ransomware operators, exploit critical Cisco FMC flaws CVE-2026-20079 and CVE-2026-20316 for root access, credential theft, and ransomware.
Cisco Talos identified three post-compromise clusters exploiting recently patched Cisco Secure Firewall Management Center flaws. UAT-12197 deploys JSP web shells and harvests credentials; UAT-11823 (with Sandworm-overlapping tooling) installs Cyclops Blink for persistence; UAT-11988 (Qilin) uses static credentials, extensive reconnaissance, SOCKS5 proxies, reverse-SSH tunnels, AV killers, and ransomware deployment. CISA added CVE-2026-20079 to the KEV catalog with a September 12, 2026 patch deadline for federal agencies; Cisco urges immediate hotfix application.
China-Linked Hackers Exploit Chrome and Windows Zero-Days in BlueMoon Attacks
China-linked clusters deploy the BlueMoon kit chaining Chrome V8 CVE-2026-85046 and Windows LPE CVE-2026-85880 in espionage campaigns.
Proofpoint researchers identified BlueMoon, an exploit kit combining a V8 type-confusion RCE (CVE-2026-85046), a V8 sandbox escape, and a Windows kernel privilege-escalation flaw (CVE-2026-85880), first observed August 28, 2026. At least four clusters adopted it, led by TA412 (also tracked as APT31/Violet Typhoon) and followed by UNK_LateNight, UNK_DoubleCheck, and UNK_QuietRacket, targeting aerospace, manufacturing, government, consulting, and financial sectors. The kit exploited a nearly four-week patch gap between the public Chromium commit (August 7) and stable rollout (September 3). TA412 delivered the GemStone Chrome extension masquerading as a Gemini companion, while other clusters deployed ShadowPad via DLL sideloading, a Rust loader, and DoH-based C2.
Keys to the Kingdom: Erlang/OTP SSH Vulnerability Analysis and Exploits Observed in the Wild
Attackers actively exploit CVE-2025-32433, a CVSS 10.0 unauthenticated RCE in Erlang/OTP SSH, heavily targeting OT and critical infrastructure networks.
CVE-2025-32433 enables unauthenticated RCE in Erlang/OTP's SSH daemon via SSH connection protocol messages (codes >= 80) processed before authentication, affecting versions before OTP-27.3.3, OTP-26.2.5.11 and OTP-25.3.2.20. Unit 42 recorded a spike in exploitation between May 1-9, 2025, with 70% of detections on firewalls protecting OT networks, disproportionately affecting healthcare, agriculture, media and high technology. Observed payloads bind TCP-connected shells or launch Bash reverse shells to hosts like 146.103.40.203:6667, with randomized DNS lookups under dns.outbound.watchtowr.com indicating OAST-driven blind RCE validation.
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.
Microsoft Patches Record 974 Flaws, Including Two Exploited Windows Zero-Days
Microsoft's September Patch Tuesday fixed a record 974 flaws, including two Windows privilege-escalation zero-days actively exploited and added to CISA's KEV catalog.
Microsoft's September 2026 Patch Tuesday addressed a record 974 vulnerabilities (999 including 25 non-Microsoft CVEs), with over 110 rated critical; 723 affect Windows and 111 affect Office. Two Windows privilege-escalation zero-days are actively exploited: CVE-2026-85880, an ALPC heap-based buffer overflow, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack, both allowing attackers to gain SYSTEM privileges. CISA added both flaws to its KEV catalog, giving federal civilian agencies until September 22, 2026 to apply fixes. Volexity, Proofpoint, MSTIC, and independent researchers were credited with the reports; notable additional fixes include network-reachable RCEs in Exchange, SharePoint, SQL Server, Remote Desktop Services, DNS, and DHCP.
Active exploitation of Cisco Secure Firewall Management Center vulnerabilities
Cisco Talos reports in-the-wild exploitation of critical FMC flaw CVE-2026-20079 by three clusters including a Sandworm-linked APT and Qilin ransomware affiliates.
Cisco Talos is tracking active exploitation of CVE-2026-20079 (CVSS 10.0), an authentication bypass in Cisco Secure Firewall Management Center that lets unauthenticated remote attackers execute scripts and obtain root access, and CVE-2026-20316 (CVSS 5.3), which permits low-privileged logins and can be chained for privilege escalation. Talos identified three post-compromise clusters: UAT-12197 deploying JSP web shells and a JAR command executor for credential theft; UAT-11823, an APT overlapping with Sandworm, deploying a Netcat reverse shell and Cyclops Blink malware; and UAT-11988, assessed as a ransomware operator with TTPs consistent with Qilin affiliates. Hotfixes are available, with a comprehensive hardening release due the week of September 14, 2026.