{"cve":{"cve_id":"CVE-2025-3935","is_kev":true,"kev_date_added":"2025-06-02","kev_vendor_project":"ConnectWise","kev_product":"ScreenConnect","kev_vulnerability_name":"ConnectWise ScreenConnect Improper Authentication Vulnerability","kev_short_description":"ConnectWise ScreenConnect contains an improper authentication vulnerability. This vulnerability could allow a ViewState code injection attack, which could allow remote code execution if machine keys are compromised.","kev_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.","kev_due_date":"2025-06-23","kev_known_ransomware":false,"kev_notes":"https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4 ;   https://nvd.nist.gov/vuln/detail/CVE-2025-3935","kev_cwes":["CWE-287"],"epss_score":0.03348,"epss_percentile":0.87107,"epss_as_of":"2026-06-23","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. \nIt is important to note that to obtain these machine keys, privileged system level access must be obtained. \n\n\n\nIf 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. \n\n\n\nThe 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.","published_at":"2025-04-25T18:27:44.244000Z","last_modified_at":null,"cvss_v3_score":8.1,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-502"],"nvd_references":["https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4","https://www.connectwise.com/company/trust/advisories"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:31.350578Z","updated_at":"2026-06-28T23:26:45.782653Z"},"effective_severity":"HIGH","badges":["kev"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"H","value_label":"High"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"connectwise","vendor_name":"ConnectWise","product_slug":"screenconnect","product_name":"ScreenConnect","version_start":"<25.2.3","version_start_inclusive":true,"version_end":"<25.2.3","version_end_inclusive":true,"cpe23_uri":"cve5:connectwise:screenconnect:<25.2.3:<25.2.3"}],"exploit_refs":[],"news":[],"references":[{"url":"https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4","source_type":"MISC","tags":["patch"]},{"url":"https://www.connectwise.com/company/trust/advisories","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2025-04-25T18:27:44.244000Z","label":"CVE published","source":null},{"type":"cisa_reported","at":"2025-06-02T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"cvss_changed","at":"2026-06-28T17:45:57.361219Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:45:57.361219Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:45:57.361219Z","label":"CVSS score revised","source":"cvelistv5"}]}