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Vulnerability record · CVE-2026-3564 · published 17 March 2026

CVE-2026-3564: Improper verification of cryptographic signature vulnerability

A condition in the ScreenConnect server component may allow an actor with access to server-level cryptographic material used for authentication to obtain unauthorized access, including elevated privileges, in certain scenarios. ScreenConnect host and guest client agents are not independently affected by this CVE.

9.0 CVSS 3.1 Critical EPSS 0.28% · top 81.2% CWE-347 · Improper verification of cryptographic signature Awaiting Analysis
9.0CVSS 3.1 base score
0.28%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
1References
9 Jul 2026Last modified by NVD

Description

A condition in the ScreenConnect server component may allow an actor with access to server-level cryptographic material used for authentication to obtain unauthorized access, including elevated privileges, in certain scenarios. ScreenConnect host and guest client agents are not independently affected by this CVE.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

References

LinkTags
https://www.connectwise.com/company/trust/security-bulletins/2026-03-17-screenconnect-bulletin

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-3564), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.