September 2026 Patch Tuesday roundup: Plugs for two zero day holes among almost 1,000 fixes in Windows
Microsoft's September 2026 Patch Tuesday ships 964 fixes including two exploited Windows zero-days (CVE-2026-85880, CVE-2026-81963) and a wormable DNS RCE.
Microsoft's September 2026 Patch Tuesday includes 964 Microsoft vulnerabilities requiring customer action, a record attributed to AI-assisted bug discovery, plus 174 third-party/open-source and 23 Chromium/Edge CVEs. Two zero-days are exploited in the wild: CVE-2026-85880, a Windows ALPC heap overflow enabling AppContainer sandbox escape and privilege escalation, and CVE-2026-81963, a Windows Update Stack escalation to SYSTEM. CVE-2026-69730, an unauthenticated Windows DNS RCE, is not yet exploited but Microsoft expects exploitation, and roughly 20 bugs could be wormable. Separately, SAP issued a critical CVSS 10.0 fix for the EPP component used in S/4HANA and NetWeaver.
Threat Actors Use Claude AI Agents to Automate Cyberattacks and Steal Sensitive Data
Anthropic reports state-linked and criminal actors used Claude AI agents to automate espionage, extortion, and exploit development, stealing 300,000+ identity records and drone IP.
Anthropic's threat report details AI-driven campaigns disrupted between December 2025 and August 2026, including suspected Russian cluster GTG-20006, which targeted Ukrainian and European governments, defense firms, and drone supply chains using fully automated attack chains. The group stole over 300,000 national identity records and commercial-registry data on 500,000+ companies from a North African government technology authority, plus a proprietary drone-vision SDK. Suspected ShinyHunters affiliates decompiled 1.8 million Android APKs on 10 Amazon EC2 workers to find hardcoded secrets and abused stolen AI API keys, while the Chinese-speaking GTG-10007 cluster generated over a dozen potential zero-day findings against network appliances in one month.
FrostyGoop’s Zoom-In: A Closer Look into the Malware Artifacts, Behaviors and Network Communications
Unit 42 dissects FrostyGoop OT malware, which sent Modbus TCP commands to disrupt heating for 600+ apartment buildings in Ukraine.
Palo Alto Unit 42 analyzed new FrostyGoop/BUSTLEBERM samples, the ninth known ICS-centric malware, first used against a Ukrainian municipal energy company by sending Modbus TCP commands to ENCO control devices. The attack caused a two-day heating outage affecting over 600 apartment buildings during sub-zero temperatures. The Go-compiled malware accepts Modbus register operations and timing parameters via command-line arguments or a JSON configuration file, uses an obscure open-source Modbus library, and checks the Windows BeingDebugged flag to evade debuggers. Unit 42 telemetry recorded over 1 million Modbus TCP devices exposed to the internet between September and October 2024.
ToxicPanda 2.0 Gets a Major Upgrade, Expanding Attacks Across 16 Countries
Zimperium documents ToxicPanda 2.0, an Android banking trojan now targeting 349 financial institutions in 16 countries via ADB privilege escalation and overlay credential theft.
Zimperium's zLabs documented ToxicPanda 2.0, an Android banking trojan expanding from 16 targeted apps to 349 financial institutions across 16 countries, with 167 remote commands. It poses as a dropper, abuses VPN permissions to block Google Play Protect while installing a hidden payload, then uses the Accessibility Service for screen monitoring and overlay-based credential theft. It automates enabling Android Wireless Debugging and completes the pairing handshake to gain ADB shell access for privilege escalation, and overlays fake lock screens to steal device PINs. Previously unfinished commands are now operational and samples are served from AWS-hosted storage buckets.
A maximum severity GitLab flaw could turn your CI/CD server into an attacker’s treasure trove
GitLab patched maximum-severity CVE-2026-85706, an unauthenticated path traversal enabling arbitrary file reads; CISA added it to KEV amid observed in-the-wild probes.
CVE-2026-85706 is a CVSS 10.0 path traversal in GitLab's repository commits API caused by improper confinement and missing authentication enforcement, allowing arbitrary file reads in a single unauthenticated HTTP request. It affects GitLab CE and EE versions 18.7 before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2, and was reported via GitLab's HackerOne bug bounty. CISA added the flaw to its Known Exploited Vulnerabilities catalog, and watchTowr Intel reports already observing in-the-wild probes; GitLab is used by roughly 50% of the Fortune 100 with over 50 million registered users. Defenders are advised to patch immediately, rotate any exposed secrets, and hunt logs for HTTP POST requests to /api/v4/projects/{id}/repository/commits/ URIs containing file.path parameters.
Attackers use rogue ScreenConnect clients to spread malware
Attackers deploy rogue ScreenConnect clients that spread VBScript malware to newly connected machines while ConnectWise patches a file-transfer flaw.
ConnectWise confirmed a file transfer flaw in ScreenConnect affecting both Cloud and On-Premise deployments, with a CVE identifier and official fix promised within the week; administrators can mitigate immediately by disabling TransferFiles (or TransferFilesInSession) in each role. Huntress documented incidents where social engineering installs rogue ScreenConnect clients that spawn Windows Script Host processes running four VBScript files (1.vbs-4.vbs), add a WindowsServiceHost registry Run key, and propagate to newly connected endpoints. Payloads enabled host profiling, persistence, additional ScreenConnect installs, tunneling, security-control changes, and cryptocurrency mining. ConnectWise has not confirmed a technical link between the flaw and this campaign.