Exfiltration refers to techniques and attributes that result or aid in the adversary removing files and information from the targeted mobile device.
In the mobile environment, mobile devices are frequently connected to networks outside enterprise control such as cellular networks or public Wi-Fi networks. Adversaries could attempt to evade detection by communicating on these networks, and potentially even by using non-Internet Protocol mechanisms such as Short Message Service (SMS). However, cellular networks often have data caps and/or extra data charges that could increase the potential for adversarial communication to be detected.
|T1438||Alternate Network Mediums||
Adversaries can communicate using cellular networks rather than enterprise Wi-Fi in order to bypass enterprise network monitoring systems. Adversaries may also communicate using other non-Internet Protocol mediums such as SMS, NFC, or Bluetooth to bypass network monitoring systems.
|T1436||Commonly Used Port||
Adversaries may communicate over a commonly used port to bypass firewalls or network detection systems and to blend with normal network activity to avoid more detailed inspection.
Data is encrypted before being exfiltrated in order to hide the information that is being exfiltrated from detection or to make the exfiltration less conspicuous upon inspection by a defender. The encryption is performed by a utility, programming library, or custom algorithm on the data itself and is considered separate from any encryption performed by the command and control or file transfer protocol. Common file formats that can encrypt files are RAR and zip.
|T1437||Standard Application Layer Protocol||
Adversaries may communicate using a common, standardized application layer protocol such as HTTP, HTTPS, SMTP, or DNS to avoid detection by blending in with existing traffic.