Query: write Sigma for Detects suspicious reconnaissance command line activity on Windows systems using Net.EXE Check if the user that executed
Matching passage: Sigma rule: Detects suspicious reconnaissance command line activity on Windows systems using Net.EXE Check if the user that executed. Logsource: windows / process_creation. Rule: title: Suspicious Group And Account Reconnaissance Activity Using Net.EXE id: d95de845-b83c-4a9a-8a6a-4fc802ebf6c0 status: test description: 'Detects suspicious reconnaissance command line activity on Windows systems using Net.EXE Check if the user that executed the commands is suspicious (e.g. service accounts, LOCAL_SYSTEM) ' references: - https://redcanary.com/blog/how-one-hospital-thwarted-a-ryuk-ransomware-outbreak/ - https://thedfirreport.com/2020/10/18/ryuk-in-5-hours/ - https://research.nccgroup.com/2022/08/19/back-in-black-unlocking-a-lockbit-3-0-ransomware-attack/ author: Florian Roth (Nextron Systems), omkar72, @svch0st, Nasreddine Bencherchali (Nextron Systems) date: 2019-01-16 modified: 2023-03-02 tags: - attack.discovery - attack.t1087.001 - attack.t1087.002 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: - \net.exe - \net1.exe - OriginalFileName: - net.exe - net1.exe selection_group_root: CommandLine|contains: - ' group ' - ' localgroup ' selection_group_flags: CommandLine|contains: - domain admins - ' administrator' - ' administrateur' - enterprise admins - Exchange Trusted Subsystem - Remote Desktop Users - Utilisateurs du Bureau à distance - Usuarios de escritorio remoto - ' /do' filter_group_add: CommandLine|contains: ' /add' selection_accounts_root: CommandLine|contains: ' accounts ' selection_accounts_flags: CommandLine|contains: ' /do' condition: selection_img and ((all of selection_group_* and not filter_group_add) or all of selection_accounts_*) falsepositives: - Inventory tool runs - Administrative activity level: medium
Near-miss passage: Sigma rule: Detects the deletion of one or more VPC Flow Logs in AWS Elastic Compute Cloud (EC2) through the DeleteFlowLogs API call. Logsource: aws / cloudtrail. Rule: title: AWS VPC Flow Logs Deleted id: e386b9b5-af12-450e-afff-761730fb8a98 status: experimental description: 'Detects the deletion of one or more VPC Flow Logs in AWS Elastic Compute Cloud (EC2) through the DeleteFlowLogs API call. Adversaries may delete flow logs to evade detection or remove evidence of network activity, hindering forensic investigations and visibility into malicious operations. ' references: - https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DeleteFlowLogs.html - https://awscli.amazonaws.com/v2/documentation/api/latest/reference/ec2/delete-flow-logs.html - https://www.elastic.co/docs/reference/security/prebuilt-rules/rules/integrations/aws/defense_evasion_ec2_flow_log_deletion author: Ivan Saakov date: 2025-10-19 tags: - attack.stealth logsource: product: aws service: cloudtrail detection: selection_event_name: eventName: DeleteFlowLogs selection_status_success: errorCode: Success selection_status_null: errorCode: null condition: selection_event_name and 1 of selection_status_* falsepositives: - During maintenance operations or testing, authorized administrators may delete VPC Flow Logs as part of routine network management or cleanup activities. level: high