cbcvebase.
CVE-2020-17136
published 2020-12-10

CVE-2020-17136: Windows Cloud Files Mini Filter Driver Elevation of Privilege Vulnerability

PriorityP355high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EXPLOIT
EPSS
13.96%
96.2th percentile
Windows Cloud Files Mini Filter Driver Elevation of Privilege Vulnerability

Affected

33 ranges· showing 25
VendorProductVersion rangeFixed in
microsoftwindows_10
microsoftwindows_10
microsoftwindows_10
microsoftwindows_10
microsoftwindows_10
microsoftwindows_10
microsoftwindows_10_version_1803>= 10.0.0 < publicationpublication
microsoftwindows_10_version_1809>= 10.0.0 < publicationpublication
microsoftwindows_10_version_1809>= 10.0.17763.0 < publicationpublication
microsoftwindows_10_version_1903_for_32-bit_systems>= 10.0.0 < publicationpublication
microsoftwindows_10_version_1903_for_arm64-based_systems>= 10.0.0 < publicationpublication
microsoftwindows_10_version_1903_for_x64-based_systems>= 10.0.0 < publicationpublication
microsoftwindows_10_version_1909>= 10.0.0 < publicationpublication
microsoftwindows_10_version_2004>= 10.0.0 < publicationpublication
microsoftwindows_10_version_20h2>= 10.0.0 < publicationpublication
microsoftwindows_server_2016
microsoftwindows_server_2016
microsoftwindows_server_2016
microsoftwindows_server_2016
microsoftwindows_server_2019>= 10.0.17763.0 < publicationpublication
microsoftwindows_server_version_2004>= 10.0.0 < publicationpublication
microsoftwindows_server_version_20h2>= 10.0.0 < publicationpublication
msrcwindows_10_version_1803
msrcwindows_10_version_1809
msrcwindows_10_version_1903

Detection & IOCsextracted from sources · hover to see the quote

filenamecldflt.sys
  • Monitor for file creation events in privileged/protected directories initiated by processes running under a standard user context but attributed to kernel-mode operations (missing IO_FORCE_ACCESS_CHECK / OBJ_FORCE_ACCESS_CHECK flags) via cldflt.sys.
  • Detect DLL hijacking attempts targeting the Microsoft Storage Spaces SMP service — watch for unexpected DLL loads by that service from non-standard or user-writable paths, which would result in code execution as NETWORK SERVICE.
  • Alert on privilege escalation from NETWORK SERVICE to SYSTEM via Named Pipe Impersonation (RPCSS Named Pipe Impersonation), which is the post-exploitation step following successful exploitation of this vulnerability.
  • ·Vulnerability affects Windows 10 v1803 and later only up to (but not including) the December 2020 patch cycle. Systems patched with December 2020 updates are not affected.
  • ·The Metasploit module is classified as a local exploit, meaning initial access to the target system is a prerequisite for exploitation.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
vendor_msrc7.8HIGH
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