CVE-2025-3935

ScreenConnect Exposure to ASP.NET ViewState Code Injection

Basic Information

CVE State
PUBLISHED
Reserved Date
April 25, 2025
Published Date
April 25, 2025
Last Updated
February 26, 2026
Vendor
ConnectWise
Product
ScreenConnect
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.
Tags
dotnet cisa

CVSS Scores

CVSS v3.1

8.1 - HIGH

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

EPSS Score

Score
12.03% (Percentile: 93.91%) as of 2026-05-31

SSVC Information

Exploitation
active
Technical Impact
total

Exploit Status

Exploited in the Wild
Yes (2026-06-01 10:31:20 UTC) Source

Known Exploited Vulnerability Information

Source Added Date
CVE 2026-06-01 10:31:13 UTC

Timeline

  • CVE ID Reserved

  • CVE Published to Public

  • Added to KEVIntel