T1560.003sub-technique of T1560 Archive Collected Data
Archive via Custom Method
Linux · macOS · Windowsnothing on this site yetT1560.003 on attack.mitre.org
An adversary may compress or encrypt data that is collected prior to exfiltration using a custom method. Adversaries may choose to use custom archival methods, such as encryption with XOR or stream ciphers implemented with no external library or utility references. Custom implementations of well-known compression algorithms have also been used.
If this is happening now
Checklists and playbooks to open while the alert is still live.
Playbook for this stage
Suspected data theft by an insider
A resignation with unusual file access, a DLP alert, or an unexplained large transfer.
how MITRE says to see it
Detect Archiving via Custom Method (T1560.003)
- Detects suspicious custom compression/encryption routines through anomalous script or binary execution that produces high-entropy files without standard archiving utilities. Correlates script execution, memory API usage (bitwise ops, CryptoAPI calls), and creation of archive-like files with uncommon headers.
- Detects custom archive routines by correlating script execution (Python, Perl, Bash) with creation of high-entropy files in temporary or user directories. Flags processes performing unusual bitwise operations or writing files without standard compression headers.
- Detects custom archiving by monitoring execution of Swift/Objective-C apps or scripts producing high-entropy files with non-standard headers. Correlates unified logs of abnormal NSFileHandle/NSData operations, memory use of XOR/bitwise operations, and file creation events.