CVE-2025-3935

Published Apr 25, 2025

Last updated 2 months ago

ScreenConnect

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-3935 affects ScreenConnect versions 25.2.3 and earlier. It is a ViewState code injection vulnerability in ASP.NET Web Forms. The ViewState feature is used to preserve the state of pages and controls, with data encoded in Base64 and protected by machine keys. If an attacker gains privileged system-level access and compromises these machine keys, they could create and send malicious ViewState data to the website. This could potentially lead to remote code execution on the server. ScreenConnect version 25.2.4 disables ViewState to remove any dependency on it.

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.
Source: 7d616e1a-3288-43b1-a0dd-0a65d3e70a49
NVD status: Analyzed

Risk scores

CVSS 3.1

Type: Primary
Base score: 7.2
Impact score: 5.9
Exploitability score: 1.2
Vector string: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Severity: HIGH

Known exploits

Data from CISA

Vulnerability name: ConnectWise ScreenConnect Improper Authentication Vulnerability
Exploit added on: Jun 2, 2025
Exploit action due: Jun 23, 2025
Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Weaknesses

7d616e1a-3288-43b1-a0dd-0a65d3e70a49: CWE-287
nvd@nist.gov: NVD-CWE-noinfo

Hype score: Not currently trending

Configurations

[
  {
    "nodes": [
      {
        "negate": false,
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:connectwise:screenconnect:*:*:*:*:*:*:*:*",
            "vulnerable": true,
            "matchCriteriaId": "552C1CC0-4F75-4C28-ACEF-EF1C1AD50EC2",
            "versionEndExcluding": "25.2.4"
          }
        ],
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.