BITS Job Persistence

Hypothesis and description

The following query identifies Microsoft Background Intelligent Transfer Service utility bitsadmin.exe scheduling a BITS job to persist on an endpoint. The query identifies the parameters used to create, resume or add a file to a BITS job. Typically seen combined in a oneliner or ran in sequence. If identified, review the BITS job created and capture any files written to disk. It is possible for BITS to be used to upload files and this may require further network data analysis to identify. You can use bitsadmin /list /verbose to list out the jobs during investigation.

Platforms: Windows
Domain: Analytic
Subtypes: Process
Submitted: 2021-05-11
Contributors: Splunk Threat Research <research@splunk.com>

ATT&CK coverage

Technique	Tactics	Coverage
T1197 BITS Jobs	Stealth (formerly Defense Evasion), Persistence	Moderate

1 technique. Links open MITRE ATT&CK.

T1197BITS Jobs

D3FEND techniques MITRE maps to this analytic

D3-PSA Process Spawn Analysis

Data model references

Fields from the CAR data model (object/action/field) the analytic reads.

Pseudocode and implementations

PseudocodePseudocode - detect a BITS job being scheduledData model: CAR native

Pseudocode implementation of the splunk search below

processes = search Process:Create
bitsadmin_commands = filter processes where (
  exe ="C:\Windows\System32\bitsadmin.exe" AND command_line includes one of [*create*, *addfile*, *setnotifyflags*, *setnotifycmdline*, *setminretrydelay*, *setcustomheaders*,*resume*])
output bitsadmin_commands

SplunkSplunk codeData model: Endpoint

To successfully implement this search you need to be ingesting information on process that include the name of the process responsible for the changes from your endpoints into the Endpoint datamodel in the Processes node.

| tstats count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name=bitsadmin.exe Processes.process IN (*create*, *addfile*, *setnotifyflags*, *setnotifycmdline*, *setminretrydelay*, *setcustomheaders*, *resume* ) by Processes.dest Processes.user Processes.parent_process Processes.process_name Processes.process Processes.process_id Processes.parent_process_id

Across MITRE's defensive frameworks

Linked through the 1 ATT&CK technique above.

Counter with D3FEND

Defensive techniques MITRE D3FEND maps to the same ATT&CK techniques.

1 more in the full list

View CAR-2021-05-004 on car.mitre.org

Hypothesis and description

Technique

Tactics

Coverage

T1197 BITS Jobs

Stealth (formerly Defense Evasion), Persistence

Moderate

Pseudocode and implementations

PseudocodePseudocode - detect a BITS job being scheduledData model: CAR native

Pseudocode implementation of the splunk search below

processes = search Process:Create
bitsadmin_commands = filter processes where (
  exe ="C:\Windows\System32\bitsadmin.exe" AND command_line includes one of [*create*, *addfile*, *setnotifyflags*, *setnotifycmdline*, *setminretrydelay*, *setcustomheaders*,*resume*])
output bitsadmin_commands

SplunkSplunk codeData model: Endpoint

| tstats count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name=bitsadmin.exe Processes.process IN (*create*, *addfile*, *setnotifyflags*, *setnotifycmdline*, *setminretrydelay*, *setcustomheaders*, *resume* ) by Processes.dest Processes.user Processes.parent_process Processes.process_name Processes.process Processes.process_id Processes.parent_process_id