Name:Windows PuTTY Suite Utility Execution id:64d5263e-0f29-4641-81ed-03b39c27ecd4 version:2 date:None author:Raven Tait, Splunk status:production type:Anomaly Description:This analytic detects the execution of programs associated with the PuTTY SSH client suite, including putty.exe, pscp.exe, plink.exe, psftp.exe, and puttygen.exe.
This activity is significant because these tools can be used to establish unauthorized remote connections, transfer files, or execute commands on remote systems.
If identified in an unusual context, such as non-administrative accounts or unexpected systems, it may indicate attempts to bypass security controls, perform lateral movement, or exfiltrate data, which could lead to further network compromise. 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.process_name IN ( "putty.exe", "pscp.exe", "plink.exe", "psftp.exe", "puttygen.exe" ) OR Processes.original_file_name IN ( "PuTTY", "PSCP", "Plink", "PSFTP", "PuTTYgen" ) )
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:Some legitimate users may run PuTTY for remote administration or secure file transfers. Filter alerts to exclude approved administrative activities. References: drilldown_searches: earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View the detection results for - "$user$" and "$dest$"' search:'%original_detection_search% | search user = "$user$" dest = "$dest$"' name:'View risk events for the last 7 days for - "$user$" and "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | 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:'7d' latest_offset:'0' analytic_story:['Command And Control', 'Active Directory Lateral Movement']
