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.
CISA Warns of N-able N-central RCE Vulnerability Exploited in the Wild
CISA added CVE-2026-86218, a CVSS 10.0 unauthenticated RCE in N-able N-central RMM, to its KEV catalog; on-premises admins must patch to 2026.3.1.14.
CISA added CVE-2026-86218, a CVSS 10.0 static code injection (CWE-96) enabling unauthenticated RCE in N-able N-central, to the Known Exploited Vulnerabilities catalog on September 8, 2026. The flaw affects all on-premises builds before 2026.3.1.14 across the 2025.4 through 2026.3 release lines; N-able shipped Hotfix 4 for 2026.3 on September 5-6, 2026. Huntress research indicates at least one customer's N-central instance was compromised on September 4, and federal civilian agencies must mitigate by September 11 under BOD 26-04. Hosted environments were patched server-side, but a compromised RMM server can serve as a single point of entry into entire MSP client bases.
N-able patches max severity N-central flaw amid ongoing attacks
N-able ships an emergency hotfix for a maximum-severity RCE flaw in its N-central RMM platform that attackers are actively exploiting.
N-able has released an emergency hotfix for a maximum-severity remote code execution vulnerability affecting its N-central remote monitoring and management (RMM) platform. The company urges customers to apply the fix immediately because attacks against N-central instances are ongoing. N-central is widely used by managed service providers, so a compromise of one deployment can expose many downstream customer environments.
N-able patches critical N-central zero-day exploited in the wild (CVE-2026-86218)
N-able shipped an emergency hotfix for CVE-2026-86218, a pre-auth RCE zero-day in N-central RMM observed exploited in the wild.
N-able released Hotfix 4 for N-central 2026.3 on September 5 (build 2026.3.1.14), fixing CVE-2026-86218, a critical pre-authenticated remote code execution flaw in its RMM platform popular with MSPs. A private customer notice marked urgent said the zero-day 'has been observed being exploited in the wild,' while the public advisory said there were no confirmed production exploits. Huntress also flagged two high-severity vulnerabilities, CVE-2026-86206 and CVE-2026-86207, which allow authentication bypass and unrestricted access; they were patched the same weekend and were discovered by Rapid7's Stephen Fewer. N-able advised auditing N-central user accounts for unexpected users.
Week in review: Firmware-level Android backdoor found on tablets, Dell zero-day exploited since 2024
Back-to-back N-able bugs send admins on a patching spree
CVE-2026-86218, a CVSS 10.0 pre-auth RCE in N-able N-central, is being exploited in the wild; Hotfix 4 mitigates it immediately.
N-able disclosed CVE-2026-86218 on September 6, a pre-authentication remote code execution flaw with CVSS 10.0 in its N-central RMM platform, and both N-able and Huntress report it is being exploited in the wild. It follows Huntress's disclosure of an exploit chain combining CVE-2026-86206 and CVE-2026-86207 that bypasses access controls to create unauthorized administrative accounts, investigated after a September 4 compromise of a fully patched customer environment. N-able has applied mitigations to all hosted N-central instances; on-premises customers must upgrade to Hotfix 4 (build 2026.3.1.14) immediately.
Week in review: Linux rootkit deployed on F5 BIG-IP APM devices, Cisco FMC bugs exploited
Weekly roundup: Cisco FMC and N-able N-central zero-days exploited in the wild, MikroTik RouterOS hijacks, Microsoft Patch Tuesday ships two exploited zero-days.
State-sponsored and financially-motivated attackers are actively exploiting CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center (FMC), alongside CVE-2026-20316. N-able issued an emergency hotfix for CVE-2026-86218, a critical pre-auth RCE in the N-central RMM platform exploited in the wild. CERT Polska disclosed six RouterOS vulnerabilities being chained to hijack internet-exposed MikroTik devices. Microsoft's September 2026 Patch Tuesday shipped a record patch count including two zero-days, while roughly 67,000 Trezor customers faced phishing after a shipping-partner breach and researchers privately disclosed a zero-click WeChat worm to Tencent.
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.
Critical N-able N-central Vulnerability and Active Exploitation
N-able N-central pre-auth RCE zero-day CVE-2026-86218 (CVSS 10.0) is exploited in the wild; on-prem admins must upgrade to 2026.3 HF4.
N-able disclosed a third N-central vulnerability, CVE-2026-86218, a pre-authentication RCE rated CVSS 10.0, and released hotfix 2026.3 HF4 superseding build 2026.3.1.13. Huntress reproduced an exploit chain involving an authentication bypass (CVE-2026-86206/CVE-2026-86207) after a fully patched customer's N-central production server was compromised on September 4. Attackers appended strings like .invalid to account names and probed the /remoteControlAction.do?method=getPierDetails endpoint; Huntress worked with Cloudflare to disable adversary tunnel infrastructure. Hosted N-central instances are already patched; on-prem administrators must upgrade immediately.
⚡ 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.
N-able ships second N-central hotfix as attackers keep exploiting CVE-2026-18577
N-able shipped a second N-central hotfix as attackers actively exploit authentication bypass CVE-2026-18577, attributed to ransomware group Storm-1175.
N-able released Hotfix 2 (N-central 2026.3.1.10) to counter ongoing exploitation of CVE-2026-18577, an authentication bypass that evades the patch for the earlier CVE-2026-18556; exploitation was first detected on August 1, 2026. Post-exploitation includes using the Take Control feature to reach managed endpoints, registering a Cloudflare tunnel service for persistence, creating a 'veeam' domain account, resetting admin passwords, and disabling Microsoft and Sophos security tooling. Microsoft analysts link the activity to Storm-1175, which now deploys a new StormEncryptor ransomware strain instead of Medusa, often reaching data exfiltration and ransomware within days. Sophos and Huntress expanded the IOCs and warned that partners who patched late should treat environments as potentially compromised.