Technique on mitre.org

T1048.003: Exfiltration Over Unencrypted Non-C2 Protocol

Adversaries may steal data by exfiltrating it over an un-encrypted network protocol other than that of the existing command and control channel. The data may also be sent to an alternate network location from the main command and control server.

Adversaries may opt to obfuscate this data, without the use of encryption, within network protocols that are natively unencrypted (such as HTTP, FTP, or DNS). This may include custom or publicly available encoding/compression algorithms (such as base64) as well as embedding data within protocol headers and fields.

Positive Technologies products that cover the technique

MaxPatrol SIEM knowledge base

remote_work: PT-CR-1937: SMB_RPC_Internet_Connection: Network interaction with an internet source via SMB or RPC that can be used by attackers to get initial access dnsmasq: PT-CR-2227: Dnsmasq_Base64_Encoded_DNS_Request_Detection: Suspicious Base64-encoded DNS requests dnsmasq: PT-CR-2203: Dnsmasq_DNS_Query_High_Frequency: Multiple DNS requests to the same domain, which may indicate that data is transferred using DNS dnsmasq: PT-CR-2200: Dnsmasq_TXT_Query_High_Frequency: An extremely high frequency of DNS requests with the TXT record type from a host in a short period of time may indicate the use of the Do-exfiltration utility mitre_attck_collection: PT-CR-1932: Copying_Files: Copying files and folders using xcopy and robocopy utilities, copy command, Copy-Item cmdlet bind: PT-CR-2193: BIND_Many_DNS_Requests_To_Single_Resource: Multiple DNS requests to one resource, which may indicate the activity of malware trying to access malicious websites or services bind: PT-CR-2195: BIND_Many_DNS_Requests_From_Single_Host: Multiple DNS requests from one host, which may indicate the start of malware that uses DNS for command and control bind: PT-CR-2196: BIND_Many_DNS_TXT_Records_Requests: Multiple DNS requests with the "TXT" record type, which may indicate the use of the Do-Exfiltration malicious utility bind: PT-CR-2191: BIND_Base64_Encoded_DNS_Request_Detection: A request for DNS parameters for a resource contains Base64 encoding. Attackers can encode requests to disguise their activity.

Detection

ID	DS0017	Data source and component	Command: Command Execution	Description	Monitor executed commands and arguments that may steal data by exfiltrating it over a symmetrically encrypted network protocol other than that of the existing command and control channel.

ID	DS0029	Data source and component	Network Traffic: Network Traffic Flow	Description	Monitor network data for uncommon data flows. Processes utilizing the network that do not normally have network communication or have never been seen before are suspicious.

ID	DS0022	Data source and component	File: File Access	Description	Monitor files viewed in isolation that may steal data by exfiltrating it over a symmetrically encrypted network protocol other than that of the existing command and control channel.

ID	DS0029	Data source and component	Network Traffic: Network Traffic Content	Description	Monitor and analyze traffic patterns and packet inspection associated to protocol(s) that do not follow the expected protocol standards and traffic flows (e.g extraneous packets that do not belong to established flows, gratuitous or anomalous traffic patterns, anomalous syntax, or structure). Consider correlation with process monitoring and command line to detect anomalous processes execution and command line arguments associated to traffic patterns (e.g. monitor anomalies in use of files that do not normally initiate connections for respective protocol(s)).

ID	DS0029	Data source and component	Network Traffic: Network Connection Creation	Description	Monitor for newly constructed network connections that are sent or received by untrusted hosts.

ID	Data source and component	Description
DS0017	Command: Command Execution	Monitor executed commands and arguments that may steal data by exfiltrating it over a symmetrically encrypted network protocol other than that of the existing command and control channel.
DS0029	Network Traffic: Network Traffic Flow	Monitor network data for uncommon data flows. Processes utilizing the network that do not normally have network communication or have never been seen before are suspicious.
DS0022	File: File Access	Monitor files viewed in isolation that may steal data by exfiltrating it over a symmetrically encrypted network protocol other than that of the existing command and control channel.
DS0029	Network Traffic: Network Traffic Content	Monitor and analyze traffic patterns and packet inspection associated to protocol(s) that do not follow the expected protocol standards and traffic flows (e.g extraneous packets that do not belong to established flows, gratuitous or anomalous traffic patterns, anomalous syntax, or structure). Consider correlation with process monitoring and command line to detect anomalous processes execution and command line arguments associated to traffic patterns (e.g. monitor anomalies in use of files that do not normally initiate connections for respective protocol(s)).
DS0029	Network Traffic: Network Connection Creation	Monitor for newly constructed network connections that are sent or received by untrusted hosts.

Mitigation

ID	M1057	Name	Data Loss Prevention	Description	Data loss prevention can detect and block sensitive data being sent over unencrypted protocols.

ID	M1031	Name	Network Intrusion Prevention	Description	Network intrusion detection and prevention systems that use network signatures to identify traffic for specific adversary command and control infrastructure and malware can be used to mitigate activity at the network level.

ID	M1037	Name	Filter Network Traffic	Description	Enforce proxies and use dedicated servers for services such as DNS and only allow those systems to communicate over respective ports/protocols, instead of all systems within a network.

ID	M1030	Name	Network Segmentation	Description	Follow best practices for network firewall configurations to allow only necessary ports and traffic to enter and exit the network.

ID	Name	Description
M1057	Data Loss Prevention	Data loss prevention can detect and block sensitive data being sent over unencrypted protocols.
M1031	Network Intrusion Prevention	Network intrusion detection and prevention systems that use network signatures to identify traffic for specific adversary command and control infrastructure and malware can be used to mitigate activity at the network level.
M1037	Filter Network Traffic	Enforce proxies and use dedicated servers for services such as DNS and only allow those systems to communicate over respective ports/protocols, instead of all systems within a network.
M1030	Network Segmentation	Follow best practices for network firewall configurations to allow only necessary ports and traffic to enter and exit the network.