cbcvebase.
CVE-2018-8589
published 2018-11-14

CVE-2018-8589: An elevation of privilege vulnerability exists when Windows improperly handles calls to Win32k.sys, aka "Windows Win32k Elevation of Privilege Vulnerability."…

PriorityP178high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2022-06-13
Exploited in the wild
EPSS
3.02%
85.9th percentile
An elevation of privilege vulnerability exists when Windows improperly handles calls to Win32k.sys, aka "Windows Win32k Elevation of Privilege Vulnerability." This affects Windows Server 2008, Windows 7, Windows Server 2008 R2.

Affected

18 ranges
VendorProductVersion rangeFixed in
microsoftwindows_7
microsoftwindows_7
microsoftwindows_server_2008
microsoftwindows_server_2008
microsoftwindows_server_2008
microsoftwindows_server_2008
microsoftwindows_server_2008
microsoftwindows_server_2008
microsoftwindows_server_2008_r2
microsoftwindows_server_2008_r2
microsoftwindows_server_2008_r2
msrcwindows_7_for_32-bit_systems_service_pack_1
msrcwindows_7_for_x64-based_systems_service_pack_1
msrcwindows_server_2008_for_32-bit_systems_service_pack_2
msrcwindows_server_2008_for_itanium-based_systems_service_pack_2
msrcwindows_server_2008_for_x64-based_systems_service_pack_2
msrcwindows_server_2008_r2_for_itanium-based_systems_service_pack_1
msrcwindows_server_2008_r2_for_x64-based_systems_service_pack_1

Detection & IOCsextracted from sources · hover to see the quote

yara
HEUR:Exploit.Win32.Generic
  • The exploit targets only 32-bit versions of Windows 7; detections should prioritize 32-bit win32k.sys call patterns on Windows 7 / Server 2008 / Server 2008 R2.
  • The vulnerability is a race condition in win32k!xxxMoveWindow triggered via WM_NCCALCSIZE message callbacks; monitor for anomalous cross-thread window-move operations and WM_NCCALCSIZE handling in win32k.
  • Exploit achieves kernel code execution by populating lParam with pointers to shellcode, which is then copied into kernel via win32k!SfnINOUTNCCALCSIZE; look for user-mode shellcode pointers being passed as lParam in WM_NCCALCSIZE messages.
  • Kaspersky AEP (Automatic Exploit Prevention) and Behavioral Detection Engine proactively detected this exploit; ensure endpoint behavioral detection is enabled for win32k exploit patterns.
  • Threat actors FruityArmor and SandCat are attributed to exploitation of CVE-2018-8589; SandCat also uses FinFisher/FinSpy and CHAINSHOT malware — correlate detections of these malware families with CVE-2018-8589 exploitation activity.
  • ·Exploitation in the wild was limited to Windows 7 (32-bit) and Windows Server 2008/2008 R2; the exploit does not affect 64-bit Windows 7 or later OS versions based on observed in-the-wild samples.
  • ·At time of discovery, victim telemetry was geographically limited to the Middle East; broader targeting cannot be ruled out.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.2HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
vulncheck7.8HIGH
cisa7.8HIGH
vendor_msrc7.8HIGH
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