Live Response API

Carbon Black EDR (Endpoint Detection and Response) is the new name for the product formerly called CB Response.

The EDR Live Response feature allows security operators to collect information and take action on remote endpoints in real time. These actions include the ability to upload, download, and remove files, retrieve and remove registry entries, dump contents of physical memory, execute and terminate processes.

The Live Response API is a subset of the broader EDR REST APIs. Authentication uses the same AuthToken Header as the EDR REST API.

The Live Response API is asynchronous; calling an API to execute a command on the remote endpoint, for example, will return immediately with a command ID. You can then poll the API using the command ID until a result status is returned.

Before any commands can be sent to an endpoint, you must first establish a “session” with a sensor. A sensor with an active session will keep an open connection to the Carbon Black server for as long as the session is active. Sessions are kept alive for a timeout period and then recycled once the timeout period has expired. All Live Response command APIs require a valid session id; an error is returned if the session has not been established or has timed out.

Note: To use the Live Response API, you must enable Live Response in your EDR server by editing the '/etc/cb/cb.conf' file by setting 'CbLREnabled=True'. Live Response is disabled by default. If you attempt to use the Live Response API without first enabling it in the 'cb.conf' file and restarting the 'cb-enterprise' services, you will receive an HTTP 412 error code. For cloud instances, please contact support to have it enabled.

Examples

View Current Sessions

To view all current sessions, use a GET command to https://<hostname>/api/v1/cblr/session. The following request will retrieve a list of currently active or recently closed sessions. Note: If you just created a session, it might show up as 'status: pending', this will transition to 'status: active' once the session is ready.

Request

$ curl -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" \ http://127.0.0.1/api/v1/cblr/session

Response

[
    {
        "status": "close",
        "sensor_id": 1,
        "supported_commands": [
            "delete file",
            "put file",
            "directory list",
            "get file",
            "kill",
            "create process",
            "process list",
            "create directory"
        ],
        "drives": [],
        "storage_size": "46636",
        "create_time": 1531841454.61905,
        "sensor_wait_timeout": 120,
        "address": "144.121.3.50",
        "check_in_timeout": 1200,
        "id": 2,
        "close_time": 1531845314.237512,
        "hostname": "devr-test",
        "storage_ttl": 7,
        "os_version": "",
        "session_timeout": 300,
        "current_working_directory": "/opt/cbsensor"
    },
    {
        "status": "pending",
        "sensor_id": 1,
        "supported_commands": [],
        "drives": [],
        "storage_size": 0,
        "create_time": 1531849564.118052,
        "sensor_wait_timeout": 120,
        "address": null,
        "check_in_timeout": 1200,
        "id": 3,
        "hostname": "devr-test",
        "storage_ttl": 7,
        "os_version": "",
        "session_timeout": 300,
        "current_working_directory": ""
    },
    {
        "status": "active",
        "sensor_id": 2,
        "supported_commands": [
            "delete file",
            "put file",
            "directory list",
            "get file",
            "kill",
            "create process",
            "process list",
            "create directory"
        ],
        "drives": [],
        "storage_size": "46858",
        "create_time": 1531849564.118052,
        "sensor_wait_timeout": 120,
        "address": "144.121.3.50",
        "check_in_timeout": 1200,
        "id": 3,
        "hostname": "devr-test",
        "storage_ttl": 7,
        "os_version": "",
        "session_timeout": 300,
        "current_working_directory": "/opt/cbsensor"
    }
]

Parameters

New to EDR 6.3

To view all active CB live response sessions, use a GET command with the parameter ?active_only=true to https://<hostname>/api/v1/cblr/session. The following request will retrieve a list of currently active sessions. This feature was added to reduce the size of the response when there are a large number of closed sessions. Note: If you just created a session, it might show up as 'status: pending', this will transition to 'status: active' once the session is ready.

If you don’t use a parameter, or use set active_only=false, it will default to View Current Sessions

Request

$ curl -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" \ http://127.0.0.1/api/v1/cblr/session?active_only=true

Response 

[
    {
        "status": "active",
        "sensor_id": 2,
        "supported_commands": [
            "delete file",
            "put file",
            "directory list",
            "get file",
            "kill",
            "create process",
            "process list",
            "create directory"
        ],
        "drives": [],
        "storage_size": "46858",
        "create_time": 1531849564.118052,
        "sensor_wait_timeout": 120,
        "address": "144.121.3.50",
        "check_in_timeout": 1200,
        "id": 3,
        "hostname": "devr-test",
        "storage_ttl": 7,
        "os_version": "",
        "session_timeout": 300,
        "current_working_directory": "/opt/cbsensor"
    }
]

Start a New Session

All CBLR activity requires you first start a session with a sensor by POSTing to /api/v1/cblr/session with requested sensor_id. Note: A live response session can be created from the CbR UI as well.

Request

$ curl -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" \ -d '{"sensor_id": 10}' http://127.0.0.1/api/v1/cblr/session

Response 

{
    "status": "pending",
    "sensor_id": 10,
    "supported_commands": [],
    "drives": [],
    "storage_size": 0,
    "create_time": 1418247933.634789,
    "sensor_wait_timeout": 120,
    "address": null,
    "check_in_timeout": 1200,
    "id": 2,
    "hostname": "WIN-EP7RMLTCLAJ",
    "storage_ttl": 7,
    "os_version": "",
    "session_timeout": 300,
    "current_working_directory": ""
}

Note: 'status' is pending and the session id is 2. Wait a few seconds, then GET 'status' of session 2.

Request

$ curl -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" \
http://127.0.0.1/api/v1/cblr/session/2

Response 

{
    "status": "active",
    "sensor_id": 10,
    "supported_commands": [
        "delete file",
        "put file",
        "reg delete key",
        "directory list",
        "reg create key",
        "get file",
        "reg enum key",
        "reg query value",
        "kill",
        "create process",
        "process list",
        "reg delete value",
        "reg set value",
        "create directory"
    ],
    "drives": ["A:\\", "C:\\", "D:\\"],
    "storage_size": 0,
    "create_time": 1418247933.634789,
    "sensor_wait_timeout": 120,
    "address": "::ffff:192.168.206.128",
    "check_in_timeout": 1200,
    "id": 2,
    "hostname": "WIN-EP7RMLTCLAJ",
    "storage_ttl": 7,
    "os_version": "",
    "session_timeout": 300,
    "current_working_directory": "C:\\Windows\\CarbonBlack"
}

Note: 'status' is active and session object now has context from the endpoint - 'supported_commands', 'current_working_directory', etc.

Issue Commands

Once a session is active, you can create commands by POSTing a command object to the session via /api/v1/cblr/session/2/command. For example, to get a process list:

Request

$ curl -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" \ -d '{"session_id": 2, "name": "process list"}' http://127.0.0.1/api/v1/cblr/session/2/command

Response 

{
    "status": "pending",
    "username": "admin",
    "sensor_id": 10,
    "create_time": 1418248098.5540111,
    "name": "process list",
    "object": null,
    "id": 1,
    "session_id": 2
}

Note: 'status' is pending and command id is 1. Wait a few seconds, then GET 'status' of command 1 in session 2.

Request

$ curl -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" \ http://127.0.0.1/api/v1/cblr/session/2/command/1

Response 

{
    "status": "complete",
    "username": "admin",
    "sensor_id": 10,
    "object": null,
    "create_time": 1418248098.5540111,
    "id": 1,
    "completion": 1418248098.5710759,
    "processes": [
        {
            "username": "NT AUTHORITY\\SYSTEM",
            "create_time": 1418247141,
            "parent_guid": "0000000a-0000-0000-0000-000000000000",
            "parent": 0,
            "sid": "s-1-5-18",
            "path": "",
            "command_line": "",
            "pid": 4,
            "proc_guid": "0000000a-0000-0004-01d0-14c0c80ce18b"
        },
        {
            "username": "NT AUTHORITY\\SYSTEM",
            "create_time": 1418247141,
            "parent_guid": "0000000a-0000-0004-01d0-14c0c80ce18b",
            "parent": 4,
            "sid": "s-1-5-18",
            "path": "c:\\windows\\system32\\smss.exe",
            "command_line": "\\systemroot\\system32\\smss.exe",
            "pid": 276,
            "proc_guid": "0000000a-0000-0114-01d0-14c0c80f42ec"
        }, ...
    ]
}

Note: 'status' is complete and the response includes a 'processes' object that contains the list of currently running processes on sensor_id 10 WIN-EP7RMLTCLAJ. Other commands function broadly the same way. See the documentation below and the python reference implementation for details. Happy hunting!

Close Sessions

To close a running session, you will need the session_id of the session you would like to close.

Request

curl -X PUT -H "Content-Type: application/json" -H "X-Auth-Token: d91b00774b2b903b49d8d9caa57ce9fcde16973a" -d '{"status": "close"}' http://127.0.0.1/api/v1/cblr/session/5

Response 

{
    "status": "active",
    "sensor_id": 1,
    "supported_commands": [
        "delete file",
        "put file",
        "directory list",
        "get file",
        "kill",
        "create process",
        "process list",
        "create directory"
    ],
    "drives": [],
    "storage_size": "81012",
    "create_time": 1531853425.390842,
    "sensor_wait_timeout": 120,
    "address": "144.121.3.50",
    "check_in_timeout": 1200,
    "id": 5,
    "close_time": 1531854097.192009,
    "hostname": "devr-test",
    "storage_ttl": 7,
    "os_version": "",
    "session_timeout": 300,
    "current_working_directory": "/opt/cbsensor"
}

Note: Status is still active, but if you request the status of the session using 'GET http://127.0.0.1/api/v1/cblr/session/5' after a few seconds, you should receive a new response.

New Response 

{
    "status": "close",
    "sensor_id": 1,
    "supported_commands": [
        "delete file",
        "put file",
        "directory list",
        "get file",
        "kill",
        "create process",
        "process list",
        "create directory"
    ],
    "drives": [],
    "storage_size": "81012",
    "create_time": 1531853425.390842,
    "sensor_wait_timeout": 120,
    "address": "144.121.3.50",
    "check_in_timeout": 1200,
    "id": 5,
    "close_time": 1531854097.192009,
    "hostname": "devr-test",
    "storage_ttl": 7,
    "os_version": "",
    "session_timeout": 300,
    "current_working_directory": "/opt/cbsensor"
}

Note: status is now closed.

API Reference

Establish Live Response Session

/api/v1/cblr/session/(id)

Supports GET, POST

  • GET - returns a list of all current session objects
  • GET - with (id) - returns a single session object if it exists
  • POST - starts a new session (given a sensor id), returns a session id

URL Parameters

  • wait: OPTIONAL True/False - Blocks the response until a session is available.

GET returns

Returns cblr_sensor session object with the following elements:

  • id: the current session id
  • sensor_id: the sensor id for this session
  • status: The current sensor live response status (“active”, “pending”, “timeout”, “inactive”, “close”) - Set status to close and PUT the object to close out the session
  • os_version: The current OS version of the sensor
  • current_working_directory: The path to the current working directory of the sensor
  • drives: An array of the logical drives available on the system
  • supported_commands: An array listing out the supported commands on the sensor (for when we support multiple commands across different architectures. Note: These are 1:1 mapped with the name in the JSON command object (below).
  • check_in_timeout: the timeout (in seconds) - how long should the CB server wait for the sensor to enter live mode (check-in) (default is wait 1200 seconds - 20 minutes)
  • session_timeout: the timeout (in seconds) that a sensor should wait between commands. If no command is issued over this timeout the sensor will quit. By default this is 8 minutes

POST accepts

The POST request accepts the following fields in a JSON payload:

  • sensor_id - the sensor id to start the session for
  • checkin_timeout (optional) (see cblr_sensor)
  • default_command_timeout (optional) (see cblr_sensor)
  • sensor_wait_timeout (optional) (see cblr_sensor)

POST returns

JSON “cblr_sensor” (see above) Note: Only the id will be set in the cblr_sensor until the session has checked in.

Reset Session Timeout

/api/v1/cblr/session/(id)/keepalive

Supports GET

Tells the server to reset the sensor “sensor_wait_timeout” if no commands have been sent to the sensor. This should be leveraged by interactive processes to keep a session alive when there is no command activity past the “sensor_wait_timeout” period. A request to the endpoint should be made in a time period less than the sensor_wait_timeout time.

Download Archive of Session Contents

/api/v1/cblr/session/(id)/archive

Supports GET

Returns a compressed archive of all the session contents: log of all commands, their results, contents of all files, etc.

Upload File to Server

/api/v1/cblr/session/(id)/file

Supports POST

  • POST - uploads a file to the EDR server, so it can be pushed to the sensor using the put file command (below).

Use a standard multipart/form-data file upload (such as used by curl’s -F command line option) to upload the file to the server with the file contents included in the file form field.

Example

To upload the file /tmp/blah.txt to the EDR server so that it can be uploaded to a remote endpoint through Live Response’s put file command:

$ curl -X POST https://127.0.0.1/api/v1/cblr/session/18/file -H X-Auth-Token:d91b00774b2b903b49d8d9caa57ce9fcde16973a -F file=@/tmp/blah.txt

{"status": 0, "file_name": "blah.txt", "size_uploaded": 15, "size": 15, "id": 5, "delete": false}

The file ID is now 5, which you can pass into the put file command (below).

Download File from Server

/api/v1/cblr/session/(id)/file/(file_id)/contents

Supports GET

  • GET - downloads the file contents specified by the file_id

Example

The following command will download the contents of file ID 5 (from above)

$ curl https://127.0.0.1/api/v1/cblr/session/18/file/5/content -H X-Auth-Token:d91b00774b2b903b49d8d9caa57ce9fcde16973a

Send Command to Endpoint

/api/v1/cblr/session/(id)/command

Supports GET, POST

  • GET - returns a list of commands in this session
  • POST - creates a new command for this session

URL Parameters

  • status: OPTIONAL completed/in progress/canceled - filter results based on command status
  • count: OPTIONAL int - limit to X results returned

See Command Objects below for command object details.

Get Status of Command

/api/v1/cblr/session/(id)/command/(cmdid)

Supports GET, PUT

  • GET - with (cmdid) - returns the status for the specified command
  • PUT - with (cmdid) - cancel the specified command if status is pending

See Command Objects below for command object details.

Get File Metadata

/api/v1/cblr/session/(id)/file/(file_id)

Supports GET, PUT

  • GET - returns a list of files for this session
  • GET - with (file_id) - returns the file object for the specified id
  • PUT - with (file_id) - deletes a file object from the server
  • DELETE - with (file_id) - deletes a file object from the server

GET returns

Returns a file object with the following fields:

  • id: the file id
  • file_name : the (remote) path of the file
  • size : the size of the file
  • size_uploaded : the size of the full uploaded (from the sensor) so far
  • status: A status code, result for the file request. 0 for success or non-zero for error.
  • delete : By default this is “false”, (on PUT) set to “true” to force file deletion

PUT this object with delete set to true or use the DELETE HTTP verb to delete a file from the server’s store.

Get File Content

/api/v1/cblr/session/(id)/file/(file_id)/content

Supports GET

Return the raw contents of the specified file.

Command Objects

The contents of the command request object will vary based on the command requested and the context. Fields present in all command objects:

  • id: id of this command
  • session_id: the id of the session
  • sensor_id: the sensor id for the session
  • command_timeout: the timeout (in seconds) that the sensor is willing to wait until the command completes.
  • status: One of the following: “in progress”, “complete”, “cancel”, “error”
  • name: The name of the command (ie “reg set”, “reg query”, “get file”….)
  • object: the object the command operates on. This is specific to the command but has meaning in a generic way for logging, and display purposes

Fields present when command completes:

  • completion_time: the time the command completed or 0 if still in progres

These are present if “error” is set in the status.

  • result_code: the result/status (0 if successful) or an error code if unsuccessful
  • result_type: “WinHresult”, “CbError”, etc
  • result_desc: Optional error string describing the error

The remaining fields are specific to each requested built-in command:

put file

  • name: “put file”
  • object: the destination path of the file
  • file_id: the file id of the file in session storage (use second api to add new files)

get file

  • name: “get file”
  • object: the source path of the file
  • offset: a byte offset to start getting the file. Supports a partial get.
  • get_count: the number of bytes to grab

Response Object

  • file_id: the file id of the file (must use second API call to obtain the file)

delete file

  • name: “delete file”
  • object: the source path of the object to delete

directory listing

  • name: “directory list”
  • object: the directory listing filter (or path)

Response Object

  • files: an array of file list objects, which contain:
    • attributes: an array of attribute strings representations of windows file attributes, with the FILE_ATfTRIBUTE_ part removed (ie DEVICE, DIRECTORY, HIDDEN, …..)
    • create_time: in unix time format
    • last_access_time: in unix time format
    • last_write_time: in unix time format
    • size: the size of the file
    • name: the name of the file
    • alt_name: the Windows “alternate name” (short name) of the file

reg enum key

  • name: “reg enum key”
  • object: the path of the key to query

Response Object

  • values: an array of registry values which contain:
    • value_type: the string representation of the registry value type (ie REG_DWORD, REG_QWORD, ….)
    • value_name: the name of the registry value
    • value_data: the data associated with the registry value
    • sub_keys : an array of subkey names (ie { “sub_keys” : [“some_sub_key” , “some_other_sub_key”]}

reg query value

  • name: “reg query value”
  • object: the path of the key + the path of the value (ie HKEY_LOCAL_MACHINE\blah\key\value)

Response Object

  • value: See the values object returned in the “values” field of reg enum key

reg create key

  • name: “reg create key”
  • object: the key path to create

reg delete key

  • name: “reg delete key”
  • object: the key path to delete

reg delete value

  • name : “reg delete value”
  • object: the path of the key + the path of the value

reg set value

  • name: “reg set value”
  • object: the path of the key + the path of the value
  • value_data: the data to set for the value. Note: If value_data is for type REG_MULTI_SZ then value_data should be an array of strings. ie “value_data” : [“string1”, “string2”, “string3”]
  • value_type: one of common reg value types (in string form). Ie REG_DWORD, REG_QWORD, REG_SZ, …..
  • overwrite: “true” or “false”. An optional parameter to specify whether to overwrite the value if it already exists (default value is “false”)

ps

  • name: “process list”
  • object: empty

Response Object

  • processes: an array of process objects which contain:
  • pid: process id
  • create_time: the creation time of the process in unix time
  • proc_guid: the process guid of the process
  • path: the execution path of the process
  • command_line: the command line of the process
  • sid: the Security Identifier (SID) of the default process token
  • username: the username of the default process token
  • parent: the pid (process id ) of the parent
  • parent_guid: the process guid of the parent process

kill

  • name: “kill”
  • object: the pid to kill

execute

  • name: “create process”
  • object: the path and command line of the executable
  • wait: “true” or “false” - An optional parameter to specify whether to wait for the process to complete execution before reporting the result
  • working_directory: An optional parameter to specify the working directory of the executable
  • output_file: An option file that STDERR and STDOUT will be redirected to.

Response Object

  • pid: the pid of the executed process
  • return_code: the return code of the process (if wait was set to “true”)

memdump

Note: Only available on EDR Server versions 5.1 and above, *and* requires that the target endpoint is running a sensor version 5.1 and above as well.
  • name: “memdump”
  • object: the path to save the resulting memory dump (on the endpoint)

Response Object

  • return_code: return code of the memory dump process
  • complete: boolean flag indicating if memory dump is completed
  • percentdone: percent of the process completed
  • dumping: boolean flag indicating if memory dump is in progress

Live Response Configuration Settings

Live Response settings can be configured on your EDR Server by editing your /etc/cb/cb.conf file. For cloud instances, please contact support to have these settings changed.

Enable/Disable CBLR

Enable/Disable CBLR functionality. Disabled by default

CbLREnabled=False
Note: EDR Global administrators can enable or disable Live Response on the Advanced Settings page (in the UI), but only if CbLREnabled is removed from cb.conf or commented out. If CbLREnabled is present in cb.conf, global administrators cannot change its state on the Advanced Settings page.

Timeout to Initialize Session

Timeout (in seconds) to wait for sensor to initialize cblr session (20 minutes).On expiration, cblr session is discarded.

CbLRCheckinTimeout=1200

Max Time

Max time (in seconds) for sensor to wait for a cblr command (5 minutes)

CbLRSessionTimeout=300

Long Poll Duration

Long poll duration (in seconds) of the sensor command query before returning keepalive

CbLRSensorWaitTimeout=120

Max Disk Space

Max disk space (in megabytes) usable by cblr functionality. When exceeded, all requests that could possibly require more disk space will be rejected. 0 indicates unlimited.

CbLRMaxStoreSizeMB=0

Default Time-to-live

Default time-to-live (in days) for session data. Unless overwritten through the API, session data will be deleted CbLrDefaultSessionTTLDays following the close of the session.

New to EDR 6.3+: Floating point values may be specified for CbLrDefaultSessionTTLDays (e.g. CbLrDefaultSessionTTLDays=0.01). Note that the thread that deletes the session data only runs hourly, so you may still need to wait up to one hour past the specified time interval for the deletion to occur.

CbLrDefaultSessionTTLDays=7

Max Sessions

cb-liveresponse will not allow more than CbLRMaxActiveSessions concurrent active sessions. Requests to create more than CbLRMaxActiveSessions will be rejected.

CbLRMaxActiveSessions=10

Last modified on February 15, 2023