ScreenConnect Exposure to ASP.NET ViewState Code Injection (ConnectWise ScreenConnect)
At a glance
- Source
- NVD
- EPSS
- EPSS 3.60 % · percentile 89 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- ConnectWise
- NVD status
- Analyzed
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.
Weaknesses (CWE)
- CWE-502 — Deserialization of Untrusted Data
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H | ConnectWise |
| CVSS 3.1 | HIGH 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · 7d616e1a-3288-43b1-a0dd-0a65d3e70a49 (Secondary) |
| CVSS 3.1 | HIGH 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2025-12502
- GCVE · GCVE-0-2025-3935
Affected configurations (NVD CPE)
cpe:2.3:a:connectwise:screenconnect:*:*:*:*:*:*:*:*< 25.2.4
Affected products
| Product | Versions |
|---|---|
| ConnectWise · ScreenConnect | affected <25.2.3 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| CISA Known Exploited Vulnerabilities | CC0 1.0 |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |