Updates to reduce duplication in the check_references code. Other updates to fix a number of issues introduced which cause Pytests to fail

This commit is contained in:
pyth0n1c
2022-07-18 15:58:12 -07:00
parent 1cdfb1916f
commit 7554992aa0
27 changed files with 85 additions and 95 deletions
@@ -86,17 +86,9 @@ class Baseline(BaseModel, SecurityContentObject):
@validator('references')
def references_check(cls, v, values):
if 'check_references' in values and values['check_references'] is False:
#Reference checking is NOT enabled
return v
elif 'check_references' not in values:
raise(Exception("Member 'check_references' missing from Baseline!"))
for reference in v:
LinkValidator.validate_reference(reference, values['name'])
return LinkValidator.SecurityContentObject_validate_references(v, values)
@validator('search')
def search_validate(cls, v, values):
@@ -133,18 +133,7 @@ class Detection(BaseModel, SecurityContentObject):
@validator('references')
def references_check(cls, v, values):
if 'check_references' in values and values['check_references'] is False:
#Reference checking is NOT enabled
return v
elif 'check_references' not in values:
raise(Exception("Member 'check_references' missing from Detection!"))
for reference in v:
LinkValidator.validate_reference(reference, values['name'])
return v
return LinkValidator.SecurityContentObject_validate_references(v, values)
@validator('search')
def search_validate(cls, v, values):
@@ -83,17 +83,7 @@ class Investigation(BaseModel, SecurityContentObject):
@validator('references')
def references_check(cls, v, values):
if 'check_references' in values and values['check_references'] is False:
#Reference checking is NOT enabled
return v
elif 'check_references' not in values:
raise(Exception("Member 'check_references' missing from Investigation!"))
for reference in v:
LinkValidator.validate_reference(reference, values['name'])
return LinkValidator.SecurityContentObject_validate_references(v, values)
@validator('search')
def search_validate(cls, v, values):
@@ -1,4 +1,3 @@
from lib2to3.pytree import Base
import re
from tracemalloc import start
from unittest.mock import DEFAULT
@@ -157,3 +156,19 @@ class LinkValidator(abc.ABC):
print(f"Link {failure.reference} invalid with HTTP Status Code [{failure.status_code}] and referenced by the following files:")
for ref in failure.referencing_files:
print(f"\t* {ref}")
@staticmethod
def SecurityContentObject_validate_references(v:list, values: dict)->list:
if 'check_references' not in values:
raise(Exception("Member 'check_references' missing from Baseline!"))
elif values['check_references'] is False:
#Reference checking is enabled
pass
elif values['check_references'] is True:
for reference in v:
LinkValidator.validate_reference(reference, values['name'])
#Remove the check_references key from the values dict so that it is not
#output by the serialization code
del values['check_references']
return v
@@ -28,15 +28,5 @@ class Playbook(BaseModel, SecurityContentObject):
@validator('references')
def references_check(cls, v, values):
if 'check_references' in values and values['check_references'] is False:
#Reference checking is NOT enabled
return v
elif 'check_references' not in values:
raise(Exception("Member 'check_references' missing from Playbook!"))
for reference in v:
LinkValidator.validate_reference(reference, values['name'])
return LinkValidator.SecurityContentObject_validate_references(v, values)
@@ -65,14 +65,4 @@ class Story(BaseModel, SecurityContentObject):
@validator('references')
def references_check(cls, v, values):
if 'check_references' in values and values['check_references'] is False:
#Reference checking is NOT enabled
return v
elif 'check_references' not in values:
raise(Exception("Member 'check_references' missing from Story!"))
for reference in v:
LinkValidator.validate_reference(reference, values['name'])
return LinkValidator.SecurityContentObject_validate_references(v, values)
@@ -1,5 +1,6 @@
import os
from re import A
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_core.application.factory.factory import FactoryInputDto
from bin.contentctl_project.contentctl_core.application.factory.factory import FactoryOutputDto
@@ -25,9 +26,9 @@ def test_factory_ESCU():
SecurityContentStoryBuilder(),
SecurityContentBaselineBuilder(),
SecurityContentInvestigationBuilder(),
SecurityContentPlaybookBuilder(),
SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT),
SecurityContentDirector(),
AttackEnrichment.get_attack_lookup()
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT)
)
output_dto = FactoryOutputDto([],[],[],[],[],[],[],[],[])
@@ -1,4 +1,5 @@
import os
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_core.application.use_cases.content_changer import ContentChanger, ContentChangerInputDto
from bin.contentctl_project.contentctl_core.application.factory.object_factory import ObjectFactoryInputDto
@@ -21,7 +22,7 @@ def test_content_changer_author_uppercase():
)
input_dto = ContentChangerInputDto(
ObjToYmlAdapter(),
ObjToYmlAdapter(input_path = SECURITY_CONTENT_ROOT),
factory_input_dto,
'example_converter_func'
)
@@ -1 +1 @@
{"baselines": [{"name": "Previously Seen Users In CloudTrail - Update", "id": "66ff71c2-7e01-47dd-a041-906688c9d322", "version": 1, "date": "2020-05-28", "author": "Rico Valdez, Splunk", "type": "Baseline", "datamodel": ["Authentication"], "description": "This search looks for CloudTrail events where a user logs into the console, then updates the baseline of the latest and earliest times, City, Region, and Country we have encountered this user in our dataset, grouped by user, within the last hour.", "search": "| tstats earliest(_time) as firstTime latest(_time) as lastTime from datamodel=Authentication where Authentication.signature=ConsoleLogin by Authentication.user Authentication.src | iplocation Authentication.src | rename Authentication.user as user Authentication.src as src | table user src City Region Country firstTime lastTime | inputlookup append=t previously_seen_users_console_logins | stats min(firstTime) as firstTime max(lastTime) as lastTime by user src City Region Country | outputlookup previously_seen_users_console_logins", "how_to_implement": "You must install and configure the Splunk Add-on for AWS (version 5.1.0 or later) and Enterprise Security 6.2, which contains the required updates to the Authentication data model for cloud use cases. Validate the user name entries in `previously_seen_users_console_logins`, which is a lookup file created by this support search.", "known_false_positives": "none", "references": [], "tags": {"analytic_story": ["Suspicious Cloud Authentication Activities"], "deployments": ["Daily Cache Updates"], "detections": ["Detect AWS Console Login by User from New Country", "Detect AWS Console Login by User from New Region", "Detect AWS Console Login by User from New City", "Detect AWS Console Login by New User", "Attempted Credential Dump From Registry via Reg exe"], "product": ["Splunk Security Analytics for AWS", "Splunk Enterprise", "Splunk Enterprise Security", "Splunk Cloud"], "required_fields": ["_time", "Authentication.signature", "Authentication.user", "Authentication.src"], "security_domain": "network"}}]}
{"baselines": [{"name": "Previously Seen Users In CloudTrail - Update", "id": "66ff71c2-7e01-47dd-a041-906688c9d322", "version": 1, "date": "2020-05-28", "author": "Rico Valdez, Splunk", "type": "Baseline", "datamodel": ["Authentication"], "description": "This search looks for CloudTrail events where a user logs into the console, then updates the baseline of the latest and earliest times, City, Region, and Country we have encountered this user in our dataset, grouped by user, within the last hour.", "search": "| tstats earliest(_time) as firstTime latest(_time) as lastTime from datamodel=Authentication where Authentication.signature=ConsoleLogin by Authentication.user Authentication.src | iplocation Authentication.src | rename Authentication.user as user Authentication.src as src | table user src City Region Country firstTime lastTime | inputlookup append=t previously_seen_users_console_logins | stats min(firstTime) as firstTime max(lastTime) as lastTime by user src City Region Country | outputlookup previously_seen_users_console_logins", "how_to_implement": "You must install and configure the Splunk Add-on for AWS (version 5.1.0 or later) and Enterprise Security 6.2, which contains the required updates to the Authentication data model for cloud use cases. Validate the user name entries in `previously_seen_users_console_logins`, which is a lookup file created by this support search.", "known_false_positives": "none", "check_references": false, "references": [], "tags": {"analytic_story": ["Suspicious Cloud Authentication Activities"], "deployments": ["Daily Cache Updates"], "detections": ["Detect AWS Console Login by User from New Country", "Detect AWS Console Login by User from New Region", "Detect AWS Console Login by User from New City", "Detect AWS Console Login by New User", "Attempted Credential Dump From Registry via Reg exe"], "product": ["Splunk Security Analytics for AWS", "Splunk Enterprise", "Splunk Enterprise Security", "Splunk Cloud"], "required_fields": ["_time", "Authentication.signature", "Authentication.user", "Authentication.src"], "security_domain": "network"}}]}
@@ -1 +1 @@
{"detections": [{"name": "Attempted Credential Dump From Registry via Reg exe", "id": "e9fb4a59-c5fb-440a-9f24-191fbc6b2911", "version": 6, "date": "2021-09-16", "author": "Patrick Bareiss, Splunk", "type": "TTP", "datamodel": ["Endpoint"], "description": "Monitor for execution of reg.exe with parameters specifying an export of keys that contain hashed credentials that attackers may try to crack offline.", "search": "| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_reg` OR `process_cmd` Processes.process=*save* (Processes.process=*HKEY_LOCAL_MACHINE\\\\Security* OR Processes.process=*HKEY_LOCAL_MACHINE\\\\SAM* OR Processes.process=*HKEY_LOCAL_MACHINE\\\\System* OR Processes.process=*HKLM\\\\Security* OR Processes.process=*HKLM\\\\System* OR Processes.process=*HKLM\\\\SAM*) by Processes.dest Processes.user Processes.parent_process Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)`| `security_content_ctime(lastTime)` | `attempted_credential_dump_from_registry_via_reg_exe_filter`", "how_to_implement": "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. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.", "known_false_positives": "None identified.", "references": ["https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1003.002/T1003.002.md#atomic-test-1---registry-dump-of-sam-creds-and-secrets"], "tags": {"name": "Attempted Credential Dump From Registry via Reg exe", "analytic_story": ["Credential Dumping", "DarkSide Ransomware"], "asset_type": "Endpoint", "automated_detection_testing": "passed", "cis20": ["CIS 3", "CIS 5", "CIS 16"], "confidence": 100, "context": ["Source:Endpoint", "Stage:Credential Access"], "dataset": ["https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1003.002/atomic_red_team/windows-sysmon.log"], "impact": 90, "kill_chain_phases": ["Actions on Objectives"], "message": "An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to export the registry keys.", "mitre_attack_id": ["T1003.002", "T1003"], "nist": ["DE.CM"], "observable": [{"name": "user", "type": "User", "role": ["Victim"]}, {"name": "dest", "type": "Hostname", "role": ["Victim"]}, {"name": "parent_process_name", "type": "Process", "role": ["Parent Process"]}, {"name": "process_name", "type": "Process", "role": ["Child Process"]}], "product": ["Splunk Enterprise", "Splunk Enterprise Security", "Splunk Cloud"], "required_fields": ["_time", "Processes.dest", "Processes.user", "Processes.parent_process_name", "Processes.parent_process", "Processes.original_file_name", "Processes.process_name", "Processes.process", "Processes.process_id", "Processes.parent_process_path", "Processes.process_path", "Processes.parent_process_id"], "risk_score": 90, "security_domain": "endpoint", "risk_severity": "high", "supported_tas": ["Splunk_TA_microsoft_sysmon"], "mitre_attack_enrichments": [{"mitre_attack_id": "T1003.002", "mitre_attack_technique": "Security Account Manager", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["Dragonfly", "GALLIUM", "Ke3chang", "Night Dragon", "Threat Group-3390", "Wizard Spider", "menuPass"]}, {"mitre_attack_id": "T1003", "mitre_attack_technique": "OS Credential Dumping", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["APT28", "APT32", "APT39", "Axiom", "Frankenstein", "Leviathan", "Poseidon Group", "Sowbug", "Suckfly", "Tonto Team"]}]}, "macros": [{"name": "process_reg", "definition": "(Processes.process_name=reg.exe OR Processes.original_file_name=reg.exe)", "description": "Matches the process with its original file name, data for this macro came from https://strontic.github.io/"}, {"name": "attempted_credential_dump_from_registry_via_reg_exe_filter", "definition": "search *", "description": "Update this macro to limit the output results to filter out false positives."}], "lookups": [], "cve_enrichment": [], "splunk_app_enrichment": [{"name": "Splunk Add-on for Sysmon", "url": "https://splunkbase.splunk.com/app/5709"}], "file_path": "/home/jhernandez/splunk/security_content/bin/contentctl_project/contentctl_infrastructure/tests/adapter/../builder/test_data/detection/valid.yml", "source": "detection"}]}
{"detections": [{"name": "Attempted Credential Dump From Registry via Reg exe", "id": "e9fb4a59-c5fb-440a-9f24-191fbc6b2911", "version": 6, "date": "2021-09-16", "author": "Patrick Bareiss, Splunk", "type": "TTP", "datamodel": ["Endpoint"], "description": "Monitor for execution of reg.exe with parameters specifying an export of keys that contain hashed credentials that attackers may try to crack offline.", "search": "| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_reg` OR `process_cmd` Processes.process=*save* (Processes.process=*HKEY_LOCAL_MACHINE\\\\Security* OR Processes.process=*HKEY_LOCAL_MACHINE\\\\SAM* OR Processes.process=*HKEY_LOCAL_MACHINE\\\\System* OR Processes.process=*HKLM\\\\Security* OR Processes.process=*HKLM\\\\System* OR Processes.process=*HKLM\\\\SAM*) by Processes.dest Processes.user Processes.parent_process Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)`| `security_content_ctime(lastTime)` | `attempted_credential_dump_from_registry_via_reg_exe_filter`", "how_to_implement": "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. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.", "known_false_positives": "None identified.", "check_references": false, "references": ["https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1003.002/T1003.002.md#atomic-test-1---registry-dump-of-sam-creds-and-secrets"], "tags": {"name": "Attempted Credential Dump From Registry via Reg exe", "analytic_story": ["Credential Dumping", "DarkSide Ransomware"], "asset_type": "Endpoint", "automated_detection_testing": "passed", "cis20": ["CIS 3", "CIS 5", "CIS 16"], "confidence": 100, "context": ["Source:Endpoint", "Stage:Credential Access"], "dataset": ["https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1003.002/atomic_red_team/windows-sysmon.log"], "impact": 90, "kill_chain_phases": ["Actions on Objectives"], "message": "An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to export the registry keys.", "mitre_attack_id": ["T1003.002", "T1003"], "nist": ["DE.CM"], "observable": [{"name": "user", "type": "User", "role": ["Victim"]}, {"name": "dest", "type": "Hostname", "role": ["Victim"]}, {"name": "parent_process_name", "type": "Process", "role": ["Parent Process"]}, {"name": "process_name", "type": "Process", "role": ["Child Process"]}], "product": ["Splunk Enterprise", "Splunk Enterprise Security", "Splunk Cloud"], "required_fields": ["_time", "Processes.dest", "Processes.user", "Processes.parent_process_name", "Processes.parent_process", "Processes.original_file_name", "Processes.process_name", "Processes.process", "Processes.process_id", "Processes.parent_process_path", "Processes.process_path", "Processes.parent_process_id"], "risk_score": 90, "security_domain": "endpoint", "risk_severity": "high", "supported_tas": ["Splunk_TA_microsoft_sysmon"], "mitre_attack_enrichments": [{"mitre_attack_id": "T1003.002", "mitre_attack_technique": "Security Account Manager", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["Dragonfly", "GALLIUM", "Ke3chang", "Night Dragon", "Threat Group-3390", "Wizard Spider", "menuPass"]}, {"mitre_attack_id": "T1003", "mitre_attack_technique": "OS Credential Dumping", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["APT28", "APT32", "APT39", "Axiom", "Frankenstein", "Leviathan", "Poseidon Group", "Sowbug", "Suckfly", "Tonto Team"]}]}, "macros": [{"name": "process_reg", "definition": "(Processes.process_name=reg.exe OR Processes.original_file_name=reg.exe)", "description": "Matches the process with its original file name, data for this macro came from https://strontic.github.io/"}, {"name": "attempted_credential_dump_from_registry_via_reg_exe_filter", "definition": "search *", "description": "Update this macro to limit the output results to filter out false positives."}], "lookups": [], "cve_enrichment": [], "splunk_app_enrichment": [{"name": "Splunk Add-on for Sysmon", "url": "https://splunkbase.splunk.com/app/5709"}], "file_path": "/private/tmp/pytest/security_content/bin/contentctl_project/contentctl_infrastructure/tests/adapter/../builder/test_data/detection/valid.yml", "source": "detection"}]}
@@ -1 +1 @@
{"response_tasks": [{"name": "Get Parent Process Info", "id": "fecf2918-670d-4f1c-872b-3d7317a41bf9", "version": 2, "date": "2019-02-28", "author": "Bhavin Patel, Splunk", "type": "Investigation", "datamodel": ["Endpoint"], "description": "This search queries the Endpoint data model to give you details about the parent process of a process running on a host which is under investigation. Enter the values of the process name in question and the dest", "search": "| tstats `security_content_summariesonly` count values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes by Processes.user Processes.parent_process_name Processes.process_name Processes.dest | `drop_dm_object_name(\"Processes\")` | search parent_process_name= $parent_process_name$ |search dest = $dest$ | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`", "how_to_implement": "You must be ingesting endpoint data that tracks process activity, including parent-child relationships from your endpoints to populate the Endpoint data model in the Processes node. The command-line arguments are mapped to the \"process\" field in the Endpoint data model.", "known_false_positives": "", "references": [], "inputs": ["parent_process_name", "dest"], "tags": {"analytic_story": ["Collection and Staging", "Command and Control", "DHS Report TA18-074A", "Disabling Security Tools", "Emotet Malware DHS Report TA18-201A ", "Hidden Cobra Malware", "Lateral Movement", "Malicious PowerShell", "Monitor for Unauthorized Software", "Netsh Abuse", "Orangeworm Attack Group", "Phishing Payloads", "Possible Backdoor Activity Associated With MUDCARP Espionage Campaigns", "Prohibited Traffic Allowed or Protocol Mismatch", "Ransomware", "SamSam Ransomware", "Suspicious Command-Line Executions", "Suspicious DNS Traffic", "Suspicious MSHTA Activity", "Suspicious WMI Use", "Suspicious Windows Registry Activities", "Unusual Processes", "Windows Defense Evasion Tactics", "Windows File Extension and Association Abuse", "Windows Log Manipulation", "Windows Persistence Techniques", "Windows Privilege Escalation", "Windows Service Abuse", "DarkSide Ransomware"], "product": ["Splunk Phantom"], "required_fields": ["_time", "Processes.user", "Processes.parent_process_name", "Processes.process_name", "Processes.dest"], "security_domain": "endpoint"}, "lowercase_name": "get_parent_process_info"}]}
{"response_tasks": [{"name": "Get Parent Process Info", "id": "fecf2918-670d-4f1c-872b-3d7317a41bf9", "version": 2, "date": "2019-02-28", "author": "Bhavin Patel, Splunk", "type": "Investigation", "datamodel": ["Endpoint"], "description": "This search queries the Endpoint data model to give you details about the parent process of a process running on a host which is under investigation. Enter the values of the process name in question and the dest", "search": "| tstats `security_content_summariesonly` count values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes by Processes.user Processes.parent_process_name Processes.process_name Processes.dest | `drop_dm_object_name(\"Processes\")` | search parent_process_name= $parent_process_name$ |search dest = $dest$ | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`", "how_to_implement": "You must be ingesting endpoint data that tracks process activity, including parent-child relationships from your endpoints to populate the Endpoint data model in the Processes node. The command-line arguments are mapped to the \"process\" field in the Endpoint data model.", "known_false_positives": "", "check_references": false, "references": [], "inputs": ["parent_process_name", "dest"], "tags": {"analytic_story": ["Collection and Staging", "Command and Control", "DHS Report TA18-074A", "Disabling Security Tools", "Emotet Malware DHS Report TA18-201A ", "Hidden Cobra Malware", "Lateral Movement", "Malicious PowerShell", "Monitor for Unauthorized Software", "Netsh Abuse", "Orangeworm Attack Group", "Phishing Payloads", "Possible Backdoor Activity Associated With MUDCARP Espionage Campaigns", "Prohibited Traffic Allowed or Protocol Mismatch", "Ransomware", "SamSam Ransomware", "Suspicious Command-Line Executions", "Suspicious DNS Traffic", "Suspicious MSHTA Activity", "Suspicious WMI Use", "Suspicious Windows Registry Activities", "Unusual Processes", "Windows Defense Evasion Tactics", "Windows File Extension and Association Abuse", "Windows Log Manipulation", "Windows Persistence Techniques", "Windows Privilege Escalation", "Windows Service Abuse", "DarkSide Ransomware"], "product": ["Splunk Phantom"], "required_fields": ["_time", "Processes.user", "Processes.parent_process_name", "Processes.process_name", "Processes.dest"], "security_domain": "endpoint"}, "lowercase_name": "get_parent_process_info"}]}
@@ -1 +1 @@
{"stories": [{"name": "DarkSide Ransomware", "id": "507edc74-13d5-4339-878e-b9114ded1f35", "version": 1, "date": "2021-05-12", "author": "Bhavin Patel, Splunk", "description": "Leverage searches that allow you to detect and investigate unusual activities that might relate to the DarkSide Ransomware", "narrative": "This story addresses Darkside ransomware. This ransomware payload has many similarities to common ransomware however there are certain items particular to it. The creation of a .TXT log that shows every item being encrypted as well as the creation of ransomware notes and files adding a machine ID created based on CRC32 checksum algorithm. This ransomware payload leaves machines in minimal operation level,enough to browse the attackers websites. A customized URI with leaked information is presented to each victim.This is the ransomware payload that shut down the Colonial pipeline. The story is composed of several detection searches covering similar items to other ransomware payloads and those particular to Darkside payload.", "references": ["https://www.splunk.com/en_us/blog/security/the-darkside-of-the-ransomware-pipeline.htmlbig-game-hunting-with-ryuk-another-lucrative-targeted-ransomware/", "https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html"], "tags": {"name": "DarkSide Ransomware", "analytic_story": "DarkSide Ransomware", "category": ["Malware"], "product": ["Splunk Enterprise", "Splunk Enterprise Security", "Splunk Cloud"], "usecase": "Advanced Threat Detection", "mitre_attack_enrichments": [{"mitre_attack_id": "T1003.002", "mitre_attack_technique": "Security Account Manager", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["Dragonfly", "GALLIUM", "Ke3chang", "Night Dragon", "Threat Group-3390", "Wizard Spider", "menuPass"]}, {"mitre_attack_id": "T1003", "mitre_attack_technique": "OS Credential Dumping", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["APT28", "APT32", "APT39", "Axiom", "Frankenstein", "Leviathan", "Poseidon Group", "Sowbug", "Suckfly", "Tonto Team"]}], "mitre_attack_tactics": ["Credential Access"], "datamodels": ["Endpoint"], "kill_chain_phases": ["Actions on Objectives"]}, "detection_names": ["ESCU - Attempted Credential Dump From Registry via Reg exe - Rule"], "investigation_names": ["ESCU - Get Parent Process Info - Response Task"], "baseline_names": ["ESCU - Baseline Of Cloud Instances Launched"], "author_company": "Splunk", "author_name": "Bhavin Patel"}]}
{"stories": [{"name": "DarkSide Ransomware", "id": "507edc74-13d5-4339-878e-b9114ded1f35", "version": 1, "date": "2021-05-12", "author": "Bhavin Patel, Splunk", "description": "Leverage searches that allow you to detect and investigate unusual activities that might relate to the DarkSide Ransomware", "narrative": "This story addresses Darkside ransomware. This ransomware payload has many similarities to common ransomware however there are certain items particular to it. The creation of a .TXT log that shows every item being encrypted as well as the creation of ransomware notes and files adding a machine ID created based on CRC32 checksum algorithm. This ransomware payload leaves machines in minimal operation level,enough to browse the attackers websites. A customized URI with leaked information is presented to each victim.This is the ransomware payload that shut down the Colonial pipeline. The story is composed of several detection searches covering similar items to other ransomware payloads and those particular to Darkside payload.", "check_references": false, "references": ["https://www.splunk.com/en_us/blog/security/the-darkside-of-the-ransomware-pipeline.htmlbig-game-hunting-with-ryuk-another-lucrative-targeted-ransomware/", "https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations"], "tags": {"name": "DarkSide Ransomware", "analytic_story": "DarkSide Ransomware", "category": ["Malware"], "product": ["Splunk Enterprise", "Splunk Enterprise Security", "Splunk Cloud"], "usecase": "Advanced Threat Detection", "mitre_attack_enrichments": [{"mitre_attack_id": "T1003.002", "mitre_attack_technique": "Security Account Manager", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["Dragonfly", "GALLIUM", "Ke3chang", "Night Dragon", "Threat Group-3390", "Wizard Spider", "menuPass"]}, {"mitre_attack_id": "T1003", "mitre_attack_technique": "OS Credential Dumping", "mitre_attack_tactics": ["Credential Access"], "mitre_attack_groups": ["APT28", "APT32", "APT39", "Axiom", "Frankenstein", "Leviathan", "Poseidon Group", "Sowbug", "Suckfly", "Tonto Team"]}], "mitre_attack_tactics": ["Credential Access"], "datamodels": ["Endpoint"], "kill_chain_phases": ["Actions on Objectives"]}, "detection_names": ["ESCU - Attempted Credential Dump From Registry via Reg exe - Rule"], "investigation_names": ["ESCU - Get Parent Process Info - Response Task"], "baseline_names": ["ESCU - Baseline Of Cloud Instances Launched"], "author_company": "Splunk", "author_name": "Bhavin Patel", "detections": [{"name": "Attempted Credential Dump From Registry via Reg exe", "source": "detection", "type": "TTP", "tags": {"mitre_attack_enrichments": [{"mitre_attack_technique": "Security Account Manager"}, {"mitre_attack_technique": "OS Credential Dumping"}]}}]}]}
@@ -36,7 +36,7 @@ This story addresses Darkside ransomware. This ransomware payload has many simil
#### Reference
* [https://www.splunk.com/en_us/blog/security/the-darkside-of-the-ransomware-pipeline.htmlbig-game-hunting-with-ryuk-another-lucrative-targeted-ransomware/](https://www.splunk.com/en_us/blog/security/the-darkside-of-the-ransomware-pipeline.htmlbig-game-hunting-with-ryuk-another-lucrative-targeted-ransomware/)
* [https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html](https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html)
* [https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations](https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations)
@@ -36,7 +36,7 @@ This story addresses Darkside ransomware. This ransomware payload has many simil
#### Reference
* [https://www.splunk.com/en_us/blog/security/the-darkside-of-the-ransomware-pipeline.htmlbig-game-hunting-with-ryuk-another-lucrative-targeted-ransomware/](https://www.splunk.com/en_us/blog/security/the-darkside-of-the-ransomware-pipeline.htmlbig-game-hunting-with-ryuk-another-lucrative-targeted-ransomware/)
* [https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html](https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html)
* [https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations](https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations)
@@ -1,5 +1,6 @@
import os
import filecmp
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.adapter.obj_to_md_adapter import ObjToMdAdapter
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_director import SecurityContentDirector
@@ -46,7 +47,7 @@ def test_svg_writer():
'../builder/test_data/test/attempted_credential_dump_from_registry_via_reg_exe.test.yml'))
test = unit_test_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -54,7 +55,7 @@ def test_svg_writer():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/detection/valid.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [], [])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [], [])
detection = detection_builder.getObject()
adapter = ObjToAttackNavAdapter()
@@ -2,6 +2,8 @@ import os
import datetime
import pytest
import filecmp
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.adapter.obj_to_conf_adapter import ObjToConfAdapter
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_director import SecurityContentDirector
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_basic_builder import SecurityContentBasicBuilder
@@ -40,7 +42,7 @@ def test_write_conf_files(patch_datetime_now):
director.constructDeployment(deployment_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/deployment/ESCU/00_default_baseline.yml'))
deployment_baseline = deployment_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -71,7 +73,7 @@ def test_write_conf_files(patch_datetime_now):
[detection], [baseline], [investigation])
story = story_builder.getObject()
output_path = os.path.join(os.path.dirname(__file__), 'data')
adapter = ObjToConfAdapter()
adapter = ObjToConfAdapter(input_path = SECURITY_CONTENT_ROOT)
adapter.writeHeaders(output_path)
adapter.writeObjects([detection, detection_deprecated], output_path, SecurityContentType.detections)
adapter.writeObjects([story], output_path, SecurityContentType.stories)
@@ -1,5 +1,6 @@
import os
import filecmp
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.adapter.obj_to_json_adapter import ObjToJsonAdapter
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_basic_builder import SecurityContentBasicBuilder
@@ -29,7 +30,7 @@ def test_write_detections():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/detection/valid.yml'), [], [], [], [],
AttackEnrichment.get_attack_lookup(), [macro], [lookup])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [macro], [lookup])
detection = detection_builder.getObject()
output_path = os.path.join(os.path.dirname(__file__), 'obj_to_json_adapter_data')
@@ -141,7 +142,7 @@ def test_write_stories():
'../builder/test_data/deployment/ESCU/00_default_baseline.yml'))
deployment_baseline = deployment_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -159,7 +160,7 @@ def test_write_stories():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/detection/valid.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [], [])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [], [])
detection = detection_builder.getObject()
investigation_builder = SecurityContentInvestigationBuilder()
@@ -1,5 +1,6 @@
import os
import filecmp
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.adapter.obj_to_md_adapter import ObjToMdAdapter
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_director import SecurityContentDirector
@@ -46,7 +47,7 @@ def test_md_writer():
'../builder/test_data/test/attempted_credential_dump_from_registry_via_reg_exe.test.yml'))
test = unit_test_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -54,15 +55,15 @@ def test_md_writer():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/detection/valid.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [], [])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [], [])
detection = detection_builder.getObject()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/detection/deprecated/detect_new_user_aws_console_login.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [], [])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [], [])
detection_deprecated = detection_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -1,5 +1,6 @@
import os
import filecmp
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.adapter.obj_to_md_adapter import ObjToMdAdapter
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_director import SecurityContentDirector
@@ -46,7 +47,7 @@ def test_svg_writer():
'../builder/test_data/test/attempted_credential_dump_from_registry_via_reg_exe.test.yml'))
test = unit_test_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -54,7 +55,7 @@ def test_svg_writer():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'../builder/test_data/detection/valid.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [], [])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [], [])
detection = detection_builder.getObject()
adapter = ObjToSvgAdapter()
@@ -1,5 +1,6 @@
import os
import filecmp
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.builder.yml_reader import YmlReader
from bin.contentctl_project.contentctl_infrastructure.adapter.obj_to_yml_adapter import ObjToYmlAdapter
@@ -12,7 +13,7 @@ def test_read_and_write_yml():
file_path = os.path.join(os.path.dirname(__file__),
'obj_to_yml_data/attempted_credential_dump_from_registry_via_reg_exe.yml')
yml_obj = YmlReader.load_file(file_path)
adapter = ObjToYmlAdapter()
adapter = ObjToYmlAdapter(input_path = SECURITY_CONTENT_ROOT)
adapter.writeObjectsInPlace([yml_obj])
ref_file_path = os.path.join(os.path.dirname(__file__),
@@ -35,7 +36,7 @@ def test_write_ssa_detection():
{}, [], [])
detection = detection_builder.getObject()
adapter = ObjToYmlAdapter()
adapter = ObjToYmlAdapter(input_path = SECURITY_CONTENT_ROOT)
adapter.writeObjects([detection], os.path.join(os.path.dirname(__file__), 'obj_to_yml_data'))
detection_file_path = os.path.join(os.path.dirname(__file__),
@@ -1,8 +1,9 @@
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_infrastructure.builder.attack_enrichment import AttackEnrichment
def test_mitre_attack_enrichment():
attack_enrichment = AttackEnrichment.get_attack_lookup()
attack_enrichment = AttackEnrichment.get_attack_lookup(SECURITY_CONTENT_ROOT)
assert attack_enrichment["T1003.002"]["technique"] == "Security Account Manager"
@@ -1,5 +1,6 @@
import pytest
import os
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
from bin.contentctl_project.contentctl_core.domain.entities.enums.enums import SecurityContentProduct
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_detection_builder import SecurityContentDetectionBuilder
@@ -12,6 +13,7 @@ from bin.contentctl_project.contentctl_infrastructure.builder.attack_enrichment
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_playbook_builder import SecurityContentPlaybookBuilder
def test_read_detection():
security_content_builder = SecurityContentDetectionBuilder()
security_content_builder.setObject(os.path.join(os.path.dirname(__file__),
@@ -112,7 +114,7 @@ def test_detection_add_rba():
def test_detection_add_playbooks():
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
playbook_builder.setObject(os.path.join(os.path.dirname(__file__),
'test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -160,7 +162,7 @@ def test_attack_enrichment():
security_content_builder = SecurityContentDetectionBuilder()
security_content_builder.setObject(os.path.join(os.path.dirname(__file__),
'test_data/detection/valid.yml'))
security_content_builder.addMitreAttackEnrichment(AttackEnrichment.get_attack_lookup())
security_content_builder.addMitreAttackEnrichment(AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT))
detection = security_content_builder.getObject()
assert detection.tags.mitre_attack_enrichments[0].dict()['mitre_attack_id'] == 'T1003.002'
@@ -1,5 +1,6 @@
import os
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
import os
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_director import SecurityContentDirector
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_basic_builder import SecurityContentBasicBuilder
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_detection_builder import SecurityContentDetectionBuilder
@@ -12,6 +13,7 @@ from bin.contentctl_project.contentctl_infrastructure.builder.attack_enrichment
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_playbook_builder import SecurityContentPlaybookBuilder
def test_construct_deployments():
director = SecurityContentDirector()
deployment_builder = SecurityContentBasicBuilder()
@@ -48,7 +50,7 @@ def test_construct_macros():
def test_construct_playbooks():
director = SecurityContentDirector()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -118,7 +120,7 @@ def test_construct_detections():
'test_data/deployment/ESCU/00_default_baseline.yml'))
deployment_baseline = deployment_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -141,7 +143,7 @@ def test_construct_detections():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'test_data/detection/valid.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [macro], [lookup])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [macro], [lookup])
detection = detection_builder.getObject()
valid_annotations = {'mitre_attack': ['T1003.002', 'T1003'],
@@ -186,7 +188,7 @@ def test_construct_stories():
'test_data/deployment/ESCU/00_default_baseline.yml'))
deployment_baseline = deployment_builder.getObject()
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
director.constructPlaybook(playbook_builder, os.path.join(os.path.dirname(__file__),
'test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -204,7 +206,7 @@ def test_construct_stories():
detection_builder = SecurityContentDetectionBuilder()
director.constructDetection(detection_builder, os.path.join(os.path.dirname(__file__),
'test_data/detection/valid.yml'), [deployment], [playbook], [baseline], [test],
AttackEnrichment.get_attack_lookup(), [], [])
AttackEnrichment.get_attack_lookup(input_path = SECURITY_CONTENT_ROOT), [], [])
detection = detection_builder.getObject()
investigation_builder = SecurityContentInvestigationBuilder()
@@ -1,11 +1,14 @@
import os
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
import os
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_playbook_builder import SecurityContentPlaybookBuilder
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_detection_builder import SecurityContentDetectionBuilder
def test_read_playbook():
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
playbook_builder.setObject(os.path.join(os.path.dirname(__file__),
'test_data/playbook/example_playbook.yml'))
playbook = playbook_builder.getObject()
@@ -15,7 +18,7 @@ def test_read_playbook():
def test_enrich_detections():
playbook_builder = SecurityContentPlaybookBuilder()
playbook_builder = SecurityContentPlaybookBuilder(input_path = SECURITY_CONTENT_ROOT)
playbook_builder.setObject(os.path.join(os.path.dirname(__file__),
'test_data/playbook/example_playbook.yml'))
playbook_builder.addDetections()
@@ -1,5 +1,6 @@
import os
from bin.contentctl_project.contentctl_infrastructure.tests.test_constants import SECURITY_CONTENT_ROOT
import os
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_story_builder import SecurityContentStoryBuilder
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_detection_builder import SecurityContentDetectionBuilder
from bin.contentctl_project.contentctl_infrastructure.builder.security_content_basic_builder import SecurityContentBasicBuilder
@@ -9,6 +10,8 @@ from bin.contentctl_project.contentctl_infrastructure.builder.security_content_b
from bin.contentctl_project.contentctl_infrastructure.builder.attack_enrichment import AttackEnrichment
def test_read_story():
story_builder = SecurityContentStoryBuilder()
story_builder.setObject(os.path.join(os.path.dirname(__file__),
@@ -23,7 +26,7 @@ def test_add_detections():
security_content_builder = SecurityContentDetectionBuilder()
security_content_builder.setObject(os.path.join(os.path.dirname(__file__),
'test_data/detection/valid.yml'))
security_content_builder.addMitreAttackEnrichment(AttackEnrichment.get_attack_lookup())
security_content_builder.addMitreAttackEnrichment(AttackEnrichment.get_attack_lookup(input_path=SECURITY_CONTENT_ROOT))
detection = security_content_builder.getObject()
story_builder = SecurityContentStoryBuilder()
@@ -0,0 +1,4 @@
#Some constants that will be used in testing
import os
SECURITY_CONTENT_ROOT = os.getcwd()