Detect Data Manipulation in CrowdStrike LogScale
Adversaries may insert, delete, or manipulate data in order to influence external outcomes or hide activity, threatening the integrity of the data. This technique encompasses three sub-techniques: Stored Data Manipulation (T1565.001), where adversaries directly alter files, databases, configuration data, or audit logs at rest; Transmitted Data Manipulation (T1565.002), where data is modified during transit via network interception or proxy manipulation; and Runtime Data Manipulation (T1565.003), where in-memory data structures or process state are altered during execution. Real-world examples include FIN13 (Elephant Beetle) injecting fraudulent financial transactions into compromised payment networks to incrementally siphon funds while mimicking legitimate processing behavior. Successful data manipulation campaigns often require prolonged access, domain-specific knowledge of the target system, and specialized tooling. The impact ranges from corrupted financial records and falsified audit trails to undermined operational decision-making and destroyed forensic evidence.
MITRE ATT&CK
- Tactic
- Impact
- Technique
- T1565 Data Manipulation
- Canonical reference
- https://attack.mitre.org/techniques/T1565/
LogScale Detection Query
// Branch 1: Audit Log Cleared — Windows Security/System Event IDs 1102 or 104
#event_simpleName = "EventLogCleared" OR
(
#event_simpleName = "SyntheticNTLM"
| EventCode in [1102, 104]
)
| table([timestamp, ComputerName, UserName, EventCode, #event_simpleName])
| eval AlertType="AuditLogCleared", AlertSeverity="Critical"
// Branch 2: Database File Tampered by Scripting Engine
// Run in LogScale as a separate query
#event_simpleName = "PeFileWritten" OR #event_simpleName = "SuspiciousFileCreation"
| TargetFileName = /\.(mdf|ldf|db|sqlite|accdb|mdb|sql|bak|dbf|frm)$/i
| ParentBaseFileName = /(powershell|cmd|wscript|cscript|mshta|python[23]?|perl|php|node|ruby|bash|sh)\.exe/i
| eval AlertType="DatabaseFileTampering", AlertSeverity="High"
| table([timestamp, ComputerName, UserName, ParentBaseFileName, TargetFileName, CommandLine, AlertType, AlertSeverity])
// Branch 3: Bulk File Modification Burst (80+ files, 3+ folders, 5 min window)
// Run in LogScale as a separate query
#event_simpleName = "PeFileWritten"
| groupBy([ComputerName, UserName, ParentBaseFileName, bin(timestamp, 5min)], function=[
count(TargetFileName, as=FileCount),
count(distinct=true, TargetDirectoryName, as=FolderCount),
collect(TargetFileName, limit=5, as=SampleFiles)
])
| FileCount > 80 AND FolderCount >= 3
| eval AlertType="BulkFileModification", AlertSeverity="Medium"
| table([timestamp, ComputerName, UserName, ParentBaseFileName, FileCount, FolderCount, SampleFiles, AlertType, AlertSeverity])
// Branch 4: Critical Path Tampering by Unexpected Process
// Run in LogScale as a separate query
#event_simpleName = "PeFileWritten"
| TargetDirectoryName = /(\\windows\\system32\\winevt\\logs|\\inetpub\\logs|\\program files\\microsoft sql server|\\windows\\system32\\config)/i
| ParentBaseFileName != /(svchost|wininit|lsass|services|csrss|MsMpEng|sqlservr|sqlagent|taskhostw|TrustedInstaller|TiWorker)\.exe/i
| eval AlertType="CriticalPathTampering", AlertSeverity="High"
| table([timestamp, ComputerName, UserName, ParentBaseFileName, TargetFileName, CommandLine, AlertType, AlertSeverity])
| sort(timestamp, order=desc)CrowdStrike LogScale (Falcon) detection for T1565 Data Manipulation using four query branches: audit log clearing via EventLogCleared events, database file tampering by scripting engines using PeFileWritten events, bulk file modification bursts aggregated over 5-minute windows, and critical system path tampering by processes not on the whitelist.
Data Sources
Required Tables
False Positives & Tuning
- Threat hunting or incident response tooling run by security analysts that legitimately reads or writes database artifacts from scripting environments during forensic investigations
- Software packaging tools that modify many files across multiple directories simultaneously during application installation or uninstallation
- Continuous integration or deployment pipelines running on endpoints that perform high-volume file writes during build artifact generation
- Authorized log archival scripts that interact with Windows Event Log paths on a scheduled maintenance cadence
Other platforms for T1565
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.
- Test 1Clear Windows Security Event Log
Expected signal: Security Event ID 1102 logged in the Security log immediately before clearing, capturing SubjectUserName and SubjectDomainName of the clearing account. Sysmon Event ID 1 (Process Create) showing wevtutil.exe execution with CommandLine 'cl Security'. Note: the Security log itself will be empty after execution — collect artifacts from SIEM/forwarded logs.
- Test 2Inject Fraudulent Record into SQLite Database via Python
Expected signal: Sysmon Event ID 1: Process Create with Image=python.exe, CommandLine containing sqlite3 and INSERT. Sysmon Event ID 11: FileCreate event for test_ledger.db in %TEMP% with python.exe as the initiating process. DeviceFileEvents: ActionType=FileCreated or FileModified, FileName=test_ledger.db, InitiatingProcessFileName=python.exe.
- Test 3Bulk File Content Modification Simulating Data Falsification
Expected signal: Multiple Sysmon Event ID 11 (FileCreate) events in rapid succession with powershell.exe as the initiating process, spanning 4 different subdirectories. DeviceFileEvents will show 100+ FileModified/FileCreated events from powershell.exe across 4+ distinct FolderPath values within a 5-minute window.
- Test 4Tamper with IIS/Web Application Log File via PowerShell
Expected signal: Sysmon Event ID 11: FileCreate with TargetFilename matching u_ex260318.log, Image=powershell.exe. DeviceFileEvents: ActionType=FileCreated or FileModified, FileName containing IIS log naming convention, InitiatingProcessFileName=powershell.exe. The file path does not match the real IIS log directory but demonstrates the process-level signal.
References (12)
- https://attack.mitre.org/techniques/T1565/
- https://attack.mitre.org/techniques/T1565/001/
- https://attack.mitre.org/techniques/T1565/002/
- https://attack.mitre.org/techniques/T1565/003/
- https://f.hubspotusercontent30.net/hubfs/8776530/Sygnia-%20Elephant%20Beetle_Jan2022.pdf
- https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/advanced-hunting-devicefileevents-table
- https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-1102
- https://learn.microsoft.com/en-us/sysinternals/downloads/sysmon
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1565/T1565.md
- https://github.com/SigmaHQ/sigma/tree/master/rules/windows/file
- https://www.cisa.gov/sites/default/files/2024-01/CISA_Techniques_for_Detecting_Data_Tampering.pdf
- https://www.mandiant.com/resources/blog/fin13-elephant-beetle-targeted-financial-frauds
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