CVE-2025-3935
Confirmed PUBLISHEDScreenConnect Exposure to ASP.NET ViewState Code Injection
1 day faster than CISA KEV
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
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.
- CVE Published
- Apr 25, 2025
- Exploitation Reported
- Jun 01, 2026
- CVSS
- 8.1 High
- EPSS
- 3.3%
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| ConnectWise |
ScreenConnect
|
<25.2.3 |
Affected |
CVE References
- connectwise.com/company/trust/security-bulletins/screenconne... connectwise.com · CVE Record https://www.connectwise.com/company/trust/security-bulletins/screenco...
- connectwise.com/company/trust/advisories connectwise.com · CVE Record https://www.connectwise.com/company/trust/advisories
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CVE First | 2026-06-01 10:31 UTC |
| CISA | 2026-06-02 14:07 UTC |
No detection artifacts or sensor request patterns are available for this CVE yet.
Check back as sensor telemetry and scanner integrations are updated.
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploitation Status
Exploited in the wild
Recorded 2026-06-01 10:31:20 UTC · CVE
Weaknesses (CWE)
-
Deserialization of Untrusted Data
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
14:07 UTC about 2 months ago14:07 UTC · about 2 months ago
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
10:31 UTC about 2 months ago10:31 UTC · about 2 months ago
Added to KEVIntel KEV Feed
High-confidence, third-party attested exploitation
-
18:27 UTC about 1 year ago18:27 UTC · about 1 year ago
CVE published
Vulnerability disclosed publicly
-
14:32 UTC about 1 year ago14:32 UTC · about 1 year ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2025-3935
{
"cve_id": "CVE-2025-3935",
"title": "ScreenConnect Exposure to ASP.NET ViewState Code Injection",
"affected_vendor": "ConnectWise",
"affected_product": "ScreenConnect",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 8.1,
"epss_score": 0.03292,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}