T1027.004 Compile After Delivery

Adversaries may attempt to make payloads difficult to discover and analyze by delivering files to victims as uncompiled code. Text-based source code files may subvert analysis and scrutiny from protections targeting executables/binaries. These payloads will need to be compiled before execution; typically via native utilities such as csc.exe or GCC/MinGW.(Citation: ClearSky MuddyWater Nov 2018)

Source code payloads may also be encrypted, encoded, and/or embedded within other files, such as those delivered as a Phishing. Payloads may also be delivered in formats unrecognizable and inherently benign to the native OS (ex: EXEs on macOS/Linux) before later being (re)compiled into a proper executable binary with a bundled compiler and execution framework.(Citation: TrendMicro WindowsAppMac)

View in MITRE ATT&CK®

GCP Mappings

Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
chronicle Chronicle technique_scores T1027.004 Compile After Delivery
Comments
Chronicle can trigger an alert based on delivery of encrypted or encoded payloads with uncompiled code. This technique was scored as minimal based on low detection coverage factor. https://github.com/chronicle/detection-rules/blob/783e0e5947774785db1c55041b70176deeca6f46/soc_prime_rules/threat_hunting/process_creation/suspicious_powershell_parameter_substring.yaral https://github.com/chronicle/detection-rules/blob/783e0e5947774785db1c55041b70176deeca6f46/soc_prime_rules/threat_hunting/process_creation/encoded_iex.yaral
References