CVE-2026-84869: critical vulnerability in ConnectWise ScreenConnect
ScreenConnect Client: Guest-to-Host File Execution via File-Transfer Actions
Published · Updated
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Prioritize patching. It under exploitation confirmed by CISA.
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
A flaw in ScreenConnect client allows someone with a remote session to transfer and run files on the host computer without permission or confirmation. This bypasses security controls meant to protect your system.
CWE-269 (Improper Access Control) and CWE-862 (Missing Authorization) enable unauthorized file transfer and execution via remote session actions. The attack requires an active remote connection but circumvents host confirmation mechanisms, allowing arbitrary code execution with host privileges.
In the same product, most dangerous first.