vulnerability
ConnectWise ScreenConnect: CVE-2025-3935: Security Fix
Severity | CVSS | Published | Added | Modified |
---|---|---|---|---|
8 | (AV:N/AC:H/Au:N/C:C/I:C/A:C) | Apr 25, 2025 | Apr 28, 2025 | Jun 3, 2025 |
Severity
8
CVSS
(AV:N/AC:H/Au:N/C:C/I:C/A:C)
Published
Apr 25, 2025
Added
Apr 28, 2025
Modified
Jun 3, 2025
Description
ScreenConnect versions 25.2.3 and earlier versions may be susceptible to a ViewState code injection attack. ASP.NET Web Forms use ViewState to preserve page and control state, with data encoded using Base64 protected by machine keys.
It is important to note that to obtain these machine keys, privileged system level access must be obtained.
If these machine keys are compromised, attackers could create and send a malicious ViewState to the website, potentially leading to remote code execution on the server.
The risk does not originate from a vulnerability introduced by ScreenConnect, but from platform level behavior. This had no direct impact to ScreenConnect Client. ScreenConnect 2025.4 patch disables ViewState and removes any dependency on it.
It is important to note that to obtain these machine keys, privileged system level access must be obtained.
If these machine keys are compromised, attackers could create and send a malicious ViewState to the website, potentially leading to remote code execution on the server.
The risk does not originate from a vulnerability introduced by ScreenConnect, but from platform level behavior. This had no direct impact to ScreenConnect Client. ScreenConnect 2025.4 patch disables ViewState and removes any dependency on it.
Solution
connectwise-screenconnect-upgrade-latest

NEW
Explore Exposure Command
Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.