Detect Archive Collected Data in CrowdStrike LogScale
Adversaries may compress and/or encrypt data that is collected prior to exfiltration. Compressing the data can help to obfuscate collected data and minimize the amount of data sent over the network. Encryption can be used to hide information that is being exfiltrated from detection or make exfiltration less conspicuous upon inspection by a defender. Both compression and encryption are done prior to exfiltration and can be performed using a utility, third-party library, or custom method. Common tools include 7-Zip, WinRAR, the Windows built-in compact and certutil utilities, PowerShell Compress-Archive and .NET IO.Compression classes, and tar/gzip/openssl on Linux and macOS. Threat actors including Dragonfly, Lazarus Group, Ember Bear, BlackByte, and Axiom have all used archiving and encryption as a pre-exfiltration staging step. Sub-techniques cover archive via utility (T1560.001), archive via library (T1560.002), and archive via custom method (T1560.003).
MITRE ATT&CK
- Tactic
- Collection
- Technique
- T1560 Archive Collected Data
- Canonical reference
- https://attack.mitre.org/techniques/T1560/
LogScale Detection Query
#event_simpleName=ProcessRollup2
| FileName = /(7z\.exe|7za\.exe|7zr\.exe|rar\.exe|winrar\.exe|powershell\.exe|pwsh\.exe|certutil\.exe)/i
| IsArchiveTool := FileName = /(7z\.exe|7za\.exe|7zr\.exe|rar\.exe|winrar\.exe)/i
| PasswordProtected := IsArchiveTool = true AND CommandLine = /(\s-hp|-pass(word)?|\s-p\S)/i
| SuspiciousParent := IsArchiveTool = true AND ParentBaseFileName = /(winword|excel|outlook|powerpnt|mshta|wscript|cscript|mmc|regsvr32|rundll32)\.exe/i
| PSCompression := FileName = /(powershell|pwsh)\.exe/i AND CommandLine = /(Compress-Archive|IO\.Compression|GZipStream|DeflateStream|ZipArchive)/i
| CertutilEncode := FileName = /certutil\.exe/i AND CommandLine = /(-encode|-decode|-encodehex)/i
| PasswordProtected = true OR SuspiciousParent = true OR PSCompression = true OR CertutilEncode = true
| DetectionType := case {
PasswordProtected = true => "Password-Protected Archive";
SuspiciousParent = true => "Archive via Suspicious Parent";
PSCompression = true => "PowerShell .NET Compression";
CertutilEncode = true => "CertUtil Encoding";
* => "Suspicious Archive Activity"
}
| select([timestamp, ComputerName, UserName, FileName, CommandLine, ParentBaseFileName, DetectionType])
| sort(timestamp, order=desc)CrowdStrike LogScale (Humio) detection for T1560 Archive Collected Data using Falcon Data Replicator ProcessRollup2 events. Assigns boolean flags for each of the four detection patterns (password-protected archives, suspicious parent ancestry, PowerShell .NET compression, CertUtil encoding) and emits a labeled DetectionType field. Leverages native Falcon telemetry fields: FileName, CommandLine, ParentBaseFileName, ComputerName, and UserName for full process lineage context.
Data Sources
Required Tables
False Positives & Tuning
- Falcon sensor telemetry from automated backup agents (e.g., Commvault, Veeam) running under SYSTEM or dedicated backup service accounts that create password-protected 7-Zip archives nightly — add an exclusion by UserName for known backup service accounts combined with a scheduled-hours filter
- PowerShell DSC (Desired State Configuration) or Azure Automation runbooks that use System.IO.Compression for MOF file packaging during configuration push operations — these typically originate from known automation account names and consistent parent process trees
- CertUtil invocations on domain controllers or PKI servers performing routine certificate issuance and encoding as part of ADCS workflows — scope exclusions to specific ComputerName patterns matching CA infrastructure hostnames
Other platforms for T1560
Testing Methodology
Validate this detection against 5 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 17-Zip Password-Protected Archive of Sensitive Directory
Expected signal: Sysmon Event ID 1: Process Create with Image ending in 7z.exe, CommandLine containing '-hp' and 'staged_exfil.zip'. Sysmon Event ID 11: File Create event for C:\Windows\Temp\staged_exfil.zip with InitiatingProcessFileName=7z.exe. Security Event ID 4688 (if process command line auditing enabled) with same details.
- Test 2PowerShell Compress-Archive Staging in Temp Directory
Expected signal: Sysmon Event ID 1: Process Create with Image=powershell.exe, CommandLine containing 'Compress-Archive' and 'C:\Windows\Temp\recent_files_staged.zip'. Sysmon Event ID 11: File Create for the zip archive. PowerShell ScriptBlock Log Event ID 4104 in Microsoft-Windows-PowerShell/Operational with full cmdlet and path.
- Test 3certutil Base64 Encode Binary File
Expected signal: Sysmon Event ID 1: Process Create with Image=certutil.exe, CommandLine containing '-encode' and 'encoded_payload.txt'. Sysmon Event ID 11: File Create for C:\Windows\Temp\encoded_payload.txt. Security Event ID 4688 with the same certutil command line if process auditing is enabled.
- Test 4Linux tar + gzip Collection and Staging
Expected signal: Auditd execve record: type=EXECVE with argv containing 'tar' 'czf' '/tmp/sys_backup_...' '/etc/passwd' '/etc/shadow'. Syslog process creation record (if auditd not deployed). File creation event for /tmp/sys_backup_*.tar.gz. If using a SIEM with Linux file integrity monitoring, alert on new file creation in /tmp matching *.tar.gz by root or privileged account.
- Test 5WinRAR Archive with Password and Locked Headers
Expected signal: Sysmon Event ID 1: Process Create with Image ending rar.exe, CommandLine containing '-hp' and 'staging.rar'. Sysmon Event ID 11: File Create for C:\ProgramData\Microsoft\staging.rar with InitiatingProcessFileName=rar.exe. Security Event ID 4688 with full command line.
References (13)
- https://attack.mitre.org/techniques/T1560/
- https://attack.mitre.org/techniques/T1560/001/
- https://attack.mitre.org/techniques/T1560/002/
- https://attack.mitre.org/techniques/T1560/003/
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1560/T1560.md
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1560.001/T1560.001.md
- https://cdn.cnn.com/cnn/2018/images/07/13/gru.indictment.pdf
- https://learn.microsoft.com/en-us/defender-endpoint/advanced-hunting-deviceprocessevents-table
- https://learn.microsoft.com/en-us/defender-endpoint/advanced-hunting-devicefileevents-table
- https://www.cisa.gov/sites/default/files/publications/AA18-074A_MAR-10135536-G.PDF
- https://securelist.com/toddycat-check-logs/110696/
- https://www.cybereason.com/blog/threat-analysis-report-bumblebee-loader-the-high-road-to-enterprise-domain-control
- https://github.com/SigmaHQ/sigma/tree/master/rules/windows/process_creation
Unlock Pro Content
Get the full detection package for T1560 including response playbook, investigation guide, and atomic red team tests.