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CVE-2026-84869: ConnectWise ScreenConnect Improper Privilege Management and Missing Authorization Vulnerability

CVE-2026-84869 is rated critical with a CVSS v3.1 base score of 9.9 and affects ConnectWise ScreenConnect. Per its scoring, it can be exploited over the network, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-09-11, which means exploitation in the wild has been observed.

Vulnerability description

A condition in the ScreenConnect client may allow files to be transferred and executed through an active remote session without authorization or Host confirmation in certain circumstances. ScreenConnect servers are not impacted.

Severity breakdown

CVSS v3.1 9.9: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
Attack complexity: Low. No special conditions; the attack can be repeated reliably.
Privileges required: Low. A basic user account is enough.
User interaction: None. No action from any user is needed.
Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-269: Improper Privilege Management

The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

CWE-862: Missing Authorization

The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

Affected products

Connectwise Screenconnect: before 26.6.5.9742