Name:Office Product Spawn CMD Process id:b8b19420-e892-11eb-9244-acde48001122 version:7 date:2024-09-30 author:Teoderick Contreras, Splunk status:production type:TTP Description:The following analytic detects an Office product spawning a CMD process, which is indicative of a macro executing shell commands to download or run malicious code. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and parent process names. This activity is significant as it often signals the execution of malicious payloads, such as those seen in Trickbot spear-phishing campaigns. If confirmed malicious, this behavior could lead to unauthorized code execution, potentially compromising the system and allowing further malicious activities. Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.parent_process_name = "winword.exe" OR Processes.parent_process_name= "excel.exe" OR Processes.parent_process_name = "powerpnt.exe" OR Processes.parent_process_name= "onenote.exe" OR Processes.parent_process_name = "onenotem.exe" OR Processes.parent_process_name = "onenoteviewer.exe" OR Processes.parent_process_name = "onenoteim.exe" OR Processes.parent_process_name = "msaccess.exe" OR Processes.parent_process_name="Graph.exe" OR Processes.parent_process_name="winproj.exe") `process_cmd` by Processes.parent_process_name Processes.parent_process Processes.process_name Processes.process Processes.process_id Processes.process_guid Processes.user Processes.dest Processes.original_file_name | `drop_dm_object_name("Processes")` | `security_content_ctime(firstTime)` |`security_content_ctime(lastTime)` | `office_product_spawn_cmd_process_filter`
how_to_implement:The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process. known_false_positives:IT or network admin may create an document automation that will run shell script. References: -https://twitter.com/cyb3rops/status/1416050325870587910?s=21 -https://bazaar.abuse.ch/sample/02cbc1ab80695fc12ff8822b926957c3a600247b9ca412a137f69cb5716c8781/ -https://www.fortinet.com/blog/threat-research/latest-remcos-rat-phishing -https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/trojanized-onenote-document-leads-to-formbook-malware/ drilldown_searches: name:'View the detection results for - "$dest$" and "$user$"' search:'%original_detection_search% | search dest = "$dest$" user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$" and "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' tags: analytic_story: - 'Trickbot' - 'DarkCrystal RAT' - 'Azorult' - 'Remcos' - 'Qakbot' - 'AgentTesla' - 'CVE-2023-21716 Word RTF Heap Corruption' - 'CVE-2023-36884 Office and Windows HTML RCE Vulnerability' - 'Warzone RAT' - 'PlugX' - 'NjRAT' asset_type:Endpoint confidence:80 impact:70 message:an office product parent process $parent_process_name$ spawn child process $process_name$ in host $dest$ mitre_attack_id: - 'T1566' - 'T1566.001' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' 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:56 security_domain:endpoint
