Detects a pagemgr.exe as mentioned in the CrowdStrike report

Hunt Hypothesis

The hypothesis is that the execution of pagemgr.exe, as noted in the CrowdStrike report, may indicate the presence of a sophisticated adversary leveraging this process for persistence or command and control activities. A SOC team should proactively hunt for this behavior in Azure Sentinel to identify potential advanced threats that may evade traditional detection methods.

YARA Rule

rule COZY_FANCY_BEAR_pagemgr_Hunt 
{

    meta:
        description = "Detects a pagemgr.exe as mentioned in the CrowdStrike report"
        author = "Florian Roth"
        reference = "https://www.crowdstrike.com/blog/bears-midst-intrusion-democratic-national-committee/"
        date = "2016-06-14"

    strings:
        $s1 = "pagemgr.exe" wide fullword

    condition:
        uint16(0) == 0x5a4d and 1 of them
}

Deployment Notes

This YARA rule can be deployed in the following contexts:

• Microsoft Defender for Endpoint — Custom indicators / advanced hunting
• Email Gateway — Attachment scanning
• File Share Monitoring — Periodic scanning of shared drives
• YARA CLI — Manual threat hunting on endpoints

This rule contains 1 string patterns in its detection logic.

References

• https://www.crowdstrike.com/blog/bears-midst-intrusion-democratic-national-committee/
• Source Rule

False Positive Guidance

• Scenario: System Update or Patching via SCCM
  Description: A legitimate system update or patching process using Microsoft System Center Configuration Manager (SCCM) may trigger the rule due to pagemgr.exe being part of the update process.
  Filter/Exclusion: Check for ProcessName containing “SystemCenter” or “SCCM” in the process tree, or filter by ParentProcessName like “setup.exe” or “msiexec.exe”.

• Scenario: Microsoft Windows Update Service
  Description: The Windows Update service may use pagemgr.exe during background updates or maintenance tasks.
  Filter/Exclusion: Filter by ProcessName containing “wuauclt.exe” or “svchost.exe” with the “Windows Update” service name.

• Scenario: Scheduled Job for Memory Management
  Description: A scheduled task running a memory management tool (e.g., pagemgr.exe) as part of a regular maintenance routine could trigger the rule.
  Filter/Exclusion: Check for CommandLine containing keywords like “scheduled task”, “maintenance”, or “memory cleanup”, or filter by User as a service account (e.g., NT SERVICE\TrustedInstaller).

• Scenario: Third-Party Memory Diagnostic Tool
  Description: A third-party memory diagnostic or performance monitoring tool (e.g., pagemgr.exe from a vendor like Microsoft or a system monitoring tool) may run legitimately.
  Filter/Exclusion: Filter by FileVersion or Company field in the process properties, or check for known legitimate tool signatures.

• Scenario: Antivirus or Endpoint Protection Scan
  Description: Some antivirus or endpoint protection tools (e.g., Microsoft Defender, CrowdStrike, or others) may use pagemgr.exe as part of their memory