ScreenConnect™ 26.1 Security Hardening
Date: 3/17/2026
Product(s): ConnectWise ScreenConnect
Severity: Important
Priority: 1 – High
Summary
ConnectWise has released a security update for ScreenConnect™ that addresses issues related to how server-level cryptographic material is protected. Earlier versions of ScreenConnect stored unique machine keys per instance within server configuration files, which under certain conditions could allow unauthorized actors to extract this material and misuse it for session authentication. ScreenConnect version 26.1 introduces enhanced protections for machine key handling, including encrypted storage and management, reducing the risk of unauthorized access in scenarios where server integrity may be compromised.
Vulnerability
CVE-2026-3564
| CWE ID | Description | Base Score | Vector |
|---|---|---|---|
| CWE-347 | Improper Verification of Cryptographic Signature | 9.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H |
Severity
Important—Vulnerabilities that could compromise confidential data or other processing resources but require additional access / privilege to do so.
Priority
1 High—Vulnerabilities that are either being targeted or have higher risk of being targeted by exploits in the wild. Recommend installing updates as emergency changes or as soon as possible (e.g., within days).
Affected versions
ScreenConnect version prior to 26.1 are impacted.
Remediation
Cloud
No action is required.
On-premise
ScreenConnect Partners:
Please upgrade to ScreenConnect version 26.1. Visit Download | ScreenConnect page to download and apply the update (access requires a valid on-premises license).
- If your license is out of maintenance, you must upgrade your license before installing the latest supported release of ScreenConnect.
- For instructions on updating to the newest release, please reference this doc: Upgrade an on-premise installation - ConnectWise
Automate On-Prem Partners with ScreenConnect Integration:
For partners using an on-premises ScreenConnect installation integrated with Automate, ScreenConnect 26.1 is available through the Automate Product Updates page.
Link to release notes: ScreenConnect 26.1 / ScreenConnect