CVE-2023-36424 CrowdStrike LogScale · LogScale

Detect CVE-2023-36424 - Microsoft Windows Out-of-Bounds Read Exploitation in CrowdStrike LogScale

Detects exploitation attempts of CVE-2023-36424, a Microsoft Windows out-of-bounds read vulnerability (CWE-125) listed in CISA's Known Exploited Vulnerabilities catalog. Out-of-bounds read vulnerabilities in Windows kernel or system components can be leveraged for privilege escalation, information disclosure, or as a stepping stone in exploit chains. This detection monitors for anomalous process behavior, crash artifacts, and privilege escalation patterns consistent with exploitation of this class of vulnerability.

MITRE ATT&CK

Tactic
Privilege Escalation Credential Access Execution

LogScale Detection Query

CrowdStrike LogScale (LogScale)
cql
#event_simpleName IN ("ProcessRollup2", "SyntheticProcessRollup2", "CrashAnalysisNotification")
| filter FileName IN ("werfault.exe", "WerFault.exe", "ReportFault.exe")
   OR (#event_simpleName = "UserLogon" AND LogonType_decimal != "5" AND NOT UserName ends with "$")
   OR (#event_simpleName = "CrashAnalysisNotification")
| eval risk_indicator = case(
    FileName IN ("werfault.exe", "WerFault.exe"), "crash_artifact",
    #event_simpleName = "CrashAnalysisNotification", "crash_notification",
    #event_simpleName = "UserLogon", "interactive_logon",
    true(), "unknown"
  )
| stats count() as event_count, values(UserName) as users, values(ComputerName) as hosts by risk_indicator, FileName
| where event_count > 0
| eval cve = "CVE-2023-36424"
| table cve, risk_indicator, FileName, event_count, users, hosts
high severity medium confidence

CrowdStrike Falcon Query Language detection for CVE-2023-36424 indicators including crash artifact process events, WerFault launches, and anomalous interactive logon patterns on Windows hosts.

Data Sources

CrowdStrike Falcon EDRCrowdStrike Process Events

Required Tables

ProcessRollup2SyntheticProcessRollup2CrashAnalysisNotificationUserLogon

False Positives & Tuning

  • WerFault.exe launches from legitimate application crashes on hosts with unstable software
  • Interactive logons by administrators during normal maintenance windows
  • Security orchestration tools that trigger crash analysis as part of automated response
  • Software testers deliberately causing application faults in QA environments

Other platforms for CVE-2023-36424


Testing Methodology

Validate this detection against 4 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.

  1. Test 1Simulate Out-of-Bounds Read Crash via Malformed Input

    Expected signal: Windows Event ID 1000 (Application Error) and 1001 (WER) in Application log; WerFault.exe process launch visible in Sysmon Event ID 1; crash dump file created in %LOCALAPPDATA%\CrashDumps

  2. Test 2Privilege Escalation Simulation Following Crash Artifact

    Expected signal: Windows Event ID 4672 (Special Privileges Assigned) in Security log; Process creation events in Sysmon for cmd.exe and powershell.exe; elevated process token in DeviceProcessEvents

  3. Test 3Memory Dump Creation Mimicking Exploit Artifact

    Expected signal: Sysmon Event ID 11 (FileCreate) for .dmp file in CrashDumps directory; DeviceFileEvents entry for the dump file creation; rundll32.exe process creation with comsvcs.dll MiniDump arguments in process telemetry

  4. Test 4WerFault.exe Manual Invocation Simulation

    Expected signal: Sysmon Event ID 1 showing WerFault.exe launched by PowerShell (non-standard parent); DeviceProcessEvents with FileName=werfault.exe and InitiatingProcessFileName=powershell.exe; potential Event ID 1001 in Application log

Unlock Pro Content

Get the full detection package for CVE-2023-36424 including response playbook, investigation guide, and atomic red team tests.

Response PlaybookInvestigation GuideHunting QueriesAtomic Red Team TestsTuning Guidance

Related Detections