Vulnerability-Lookup

BDU:2025-06256

Vulnerability from fstec - Published: 24.04.2025

Title

Уязвимость механизма ViewState программного средства организации удалённого доступа ConnectWise ScreenConnect, позволяющая нарушителю выполнить произвольный код

Description

Уязвимость механизма ViewState программного средства организации удалённого доступа ConnectWise ScreenConnect связана с недостатками процедуры аутентификации. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, выполнить произвольный код путем отправки специально сформированного запроса ViewState

Severity ?


                    
                      AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Vendor

ConnectWise, LLC.

Software Name

ConnectWise ScreenConnect

Software Version

до 25.2.4 (ConnectWise ScreenConnect)

Possible Mitigations

Установка обновлений из доверенных источников. В связи со сложившейся обстановкой и введенными санкциями против Российской Федерации рекомендуется устанавливать обновления программного обеспечения только после оценки всех сопутствующих рисков. Компенсирующие меры: - использование межсетевого экрана уровня приложений (WAF) для фильтрации сетевого трафика; - использование систем обнаружения и предотвращения вторжений для обнаружения (выявления, регистрации) и реагирования на попытки эксплуатации уязвимостей; - использование SIEM-систем для отслеживания попыток эксплуатации уязвимости; - использование виртуальных частных сетей для организации удаленного доступа (VPN). Использование рекомендаций: https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4

Reference

https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4

CWE

CWE-287

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:H/Au:N/C:C/I:C/A:C",
  "CVSS 3.0": "AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "ConnectWise, LLC.",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "\u0434\u043e 25.2.4 (ConnectWise ScreenConnect)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0423\u0441\u0442\u0430\u043d\u043e\u0432\u043a\u0430 \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0439 \u0438\u0437 \u0434\u043e\u0432\u0435\u0440\u0435\u043d\u043d\u044b\u0445 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u043e\u0432. \u0412 \u0441\u0432\u044f\u0437\u0438 \u0441\u043e \u0441\u043b\u043e\u0436\u0438\u0432\u0448\u0435\u0439\u0441\u044f \u043e\u0431\u0441\u0442\u0430\u043d\u043e\u0432\u043a\u043e\u0439 \u0438 \u0432\u0432\u0435\u0434\u0435\u043d\u043d\u044b\u043c\u0438 \u0441\u0430\u043d\u043a\u0446\u0438\u044f\u043c\u0438 \u043f\u0440\u043e\u0442\u0438\u0432 \u0420\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u043e\u0439 \u0424\u0435\u0434\u0435\u0440\u0430\u0446\u0438\u0438 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0443\u0435\u0442\u0441\u044f \u0443\u0441\u0442\u0430\u043d\u0430\u0432\u043b\u0438\u0432\u0430\u0442\u044c \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f \u0442\u043e\u043b\u044c\u043a\u043e \u043f\u043e\u0441\u043b\u0435 \u043e\u0446\u0435\u043d\u043a\u0438 \u0432\u0441\u0435\u0445 \u0441\u043e\u043f\u0443\u0442\u0441\u0442\u0432\u0443\u044e\u0449\u0438\u0445 \u0440\u0438\u0441\u043a\u043e\u0432.\n\n\u041a\u043e\u043c\u043f\u0435\u043d\u0441\u0438\u0440\u0443\u044e\u0449\u0438\u0435 \u043c\u0435\u0440\u044b:\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u043c\u0435\u0436\u0441\u0435\u0442\u0435\u0432\u043e\u0433\u043e \u044d\u043a\u0440\u0430\u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u044f \u043f\u0440\u0438\u043b\u043e\u0436\u0435\u043d\u0438\u0439 (WAF) \u0434\u043b\u044f \u0444\u0438\u043b\u044c\u0442\u0440\u0430\u0446\u0438\u0438 \u0441\u0435\u0442\u0435\u0432\u043e\u0433\u043e \u0442\u0440\u0430\u0444\u0438\u043a\u0430;\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u0431\u043d\u0430\u0440\u0443\u0436\u0435\u043d\u0438\u044f \u0438 \u043f\u0440\u0435\u0434\u043e\u0442\u0432\u0440\u0430\u0449\u0435\u043d\u0438\u044f \u0432\u0442\u043e\u0440\u0436\u0435\u043d\u0438\u0439 \u0434\u043b\u044f \u043e\u0431\u043d\u0430\u0440\u0443\u0436\u0435\u043d\u0438\u044f (\u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f, \u0440\u0435\u0433\u0438\u0441\u0442\u0440\u0430\u0446\u0438\u0438) \u0438 \u0440\u0435\u0430\u0433\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u043d\u0430 \u043f\u043e\u043f\u044b\u0442\u043a\u0438 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439;\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 SIEM-\u0441\u0438\u0441\u0442\u0435\u043c \u0434\u043b\u044f \u043e\u0442\u0441\u043b\u0435\u0436\u0438\u0432\u0430\u043d\u0438\u044f \u043f\u043e\u043f\u044b\u0442\u043e\u043a \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438;\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u044c\u043d\u044b\u0445 \u0447\u0430\u0441\u0442\u043d\u044b\u0445 \u0441\u0435\u0442\u0435\u0439 \u0434\u043b\u044f \u043e\u0440\u0433\u0430\u043d\u0438\u0437\u0430\u0446\u0438\u0438 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e\u0433\u043e \u0434\u043e\u0441\u0442\u0443\u043f\u0430 (VPN).\n\n\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\nhttps://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "24.04.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "02.06.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "02.06.2025",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2025-06256",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2025-3935",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "ConnectWise ScreenConnect",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": null,
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043c\u0435\u0445\u0430\u043d\u0438\u0437\u043c\u0430 ViewState \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430 \u043e\u0440\u0433\u0430\u043d\u0438\u0437\u0430\u0446\u0438\u0438 \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e\u0433\u043e \u0434\u043e\u0441\u0442\u0443\u043f\u0430 ConnectWise ScreenConnect, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u043b\u044c\u043d\u044b\u0439 \u043a\u043e\u0434",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0421\u0443\u0449\u0435\u0441\u0442\u0432\u0443\u0435\u0442",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u0430\u044f \u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u044f (CWE-287)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043c\u0435\u0445\u0430\u043d\u0438\u0437\u043c\u0430 ViewState \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430 \u043e\u0440\u0433\u0430\u043d\u0438\u0437\u0430\u0446\u0438\u0438 \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e\u0433\u043e \u0434\u043e\u0441\u0442\u0443\u043f\u0430 ConnectWise ScreenConnect \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043a\u0430\u043c\u0438 \u043f\u0440\u043e\u0446\u0435\u0434\u0443\u0440\u044b \u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u0438. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e, \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u043b\u044c\u043d\u044b\u0439 \u043a\u043e\u0434 \u043f\u0443\u0442\u0435\u043c \u043e\u0442\u043f\u0440\u0430\u0432\u043a\u0438 \u0441\u043f\u0435\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u0441\u0444\u043e\u0440\u043c\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u043e\u0433\u043e \u0437\u0430\u043f\u0440\u043e\u0441\u0430 ViewState",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u041d\u0430\u0440\u0443\u0448\u0435\u043d\u0438\u0435 \u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u0438",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://www.connectwise.com/company/trust/security-bulletins/screenconnect-security-patch-2025.4",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u0421\u0435\u0442\u0435\u0432\u043e\u0435 \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u043e, \u0421\u0435\u0442\u0435\u0432\u043e\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0435 \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u043e",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-287",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,6)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 8,1)"
}

CVE-2025-3935 (GCVE-0-2025-3935)

Vulnerability from cvelistv5 – Published: 2025-04-25 18:27 – Updated: 2026-02-26 18:28

Title

ScreenConnect Exposure to ASP.NET ViewState Code Injection

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.

Severity ?

8.1 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE

CWE-502 - Deserialization of Untrusted Data

Assigner

ConnectWise

References

URL

Tags

	https://www.connectwise.com/company/trust/securit…
	https://www.connectwise.com/company/trust/advisories

Impacted products

	Vendor	Product	Version
	ConnectWise	ScreenConnect	Affected: <25.2.3

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

BDU:2025-06256

CVE-2025-3935 (GCVE-0-2025-3935)

Tags

Sightings

Nomenclature