tElockv080 | SOC Hunt Feed

Hunt Hypothesis

This detection identifies potential file-based threats or specific malware signatures matching the tElockv080 YARA pattern within Azure Sentinel’s workload data. Proactive hunting for this rule is essential to uncover stealthy, low-severity anomalies that may indicate early-stage compromise attempts before they escalate into critical incidents.

YARA Rule

rule tElockv080
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 60 E8 F9 11 00 00 C3 83 }

condition:
		$a0 at pe.entry_point
}

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.

Source Rule

False Positive Guidance

Here are 5 specific false positive scenarios for the tElockv080 detection rule, tailored for a legitimate enterprise environment:

Scenario: Automated Endpoint Protection Scans by CrowdStrike Falcon or Microsoft Defender for Endpoint.
- Context: During scheduled full-system scans, these agents often spawn temporary child processes to lock and analyze specific registry keys or file handles, mimicking the behavior pattern detected by tElockv080.
- Filter/Exclusion: Exclude process paths containing \Program Files\CrowdStrike\ or \Windows\System32\coresec.dll (Defender) where the parent process is falcon.sys or MsMpEng.exe.
Scenario: Scheduled Group Policy Update Tasks via Windows Task Scheduler.
- Context: The “Group Policy Client” service (gpupdate) frequently locks configuration files in %SystemRoot%\System32\gpo during policy refresh cycles, triggering the rule when it attempts to modify locked GPO artifacts.
- Filter/Exclusion: Create a whitelist for the process gpsvc.exe running under the context of the “System” account, specifically targeting file paths ending in .xml or .inf within the gpcfg directory.
Scenario: Database Backup Jobs Executed by Veeam or Commvault.
- Context: Enterprise backup agents often lock database files (e.g., SQL Server .mdf or Oracle datafiles) to ensure consistency during snapshot creation, which generates the specific locking signatures identified by this rule.
- Filter/Exclusion: Filter out events where the parent process is Veeam.Backup.Service.exe or CommServe.exe, and the target file extension matches .bak, .vmdk, or database-specific extensions like .ndf.
**Scenario