CVE-2025-3935 (GCVE-0-2025-3935)
Vulnerability from cvelistv5
Published
2025-04-25 18:27
Modified
2025-09-03 16:31
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-502 - Deserialization of Untrusted Data
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| ConnectWise | ScreenConnect |
Version: <25.2.3 |
CISA Known exploited vulnerability
Data from the Known Exploited Vulnerabilities Catalog
Date added: 2025-06-02
Due date: 2025-06-23
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.
Used in ransomware: Unknown
Notes: https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4 ; https://nvd.nist.gov/vuln/detail/CVE-2025-3935
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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