ATT&CK coverage › Technique

System Network Connections Discovery `T1049`

Adversaries may attempt to get a listing of network connections to or from the compromised system they are currently accessing or from remote systems by querying for information over the network.

Events covered

5 catalog events are tagged with this technique by at least one rule.

Provider	Event ID	Title
Sysmon	1	Process creation
Security-Auditing	4688	A new process has been created.
PowerShell	4103	Payload Context: ContextInfo User Data: UserData.
PowerShell	4104	Creating Scriptblock text (MessageNumber of MessageTotal).
PowerShell	400

Authoring guide

Patterns shared across the 6 rules above: which fields they filter on, what specific values they look for, and what they exclude. Field names are normalized across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (7 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

Field	Rules	How	Sample values
`Image`	2	`ends_with` 2	`\SharpView.exe`, `\net.exe`, `\net1.exe`
`OriginalFileName`	2	`eq` 2	`SharpView.exe`, `net.exe`, `net1.exe`
`CommandLine`	2	`match` 2, `ends_with` 1	`Get-DomainForeign`, `Get-DFSshare`, `ConvertFrom-UACValue`, `use` , `sessions`
`Data`	1	`match` 1	`Get-NetTCPConnection`
`ContextInfo`	1	`match` 1	`Get-NetTCPConnection`
`ScriptBlockText`	1	`eq` 1	`"Get-NetTcpconnection"`
`EventID`	1	`eq` 1	`4104`

Top indicator values (96 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique.

Field	Kind	Value	Rules (here)	Corpus reach
`CommandLine`	`match`	`Get-DomainFileServer`	1
`CommandLine`	`match`	`Get-LastLoggedOn`	1
`CommandLine`	`match`	`Set-DomainObject`	1
`CommandLine`	`match`	`Get-NetSite`	1
`CommandLine`	`match`	`Get-DomainDFSShare`	1
`CommandLine`	`match`	`Invoke-ACLScanner`	1	2
`CommandLine`	`match`	`Get-NetDomain`	1
`CommandLine`	`match`	`Get-NetShare`	1
`Image`	`ends_with`	`\SharpView.exe`	1	2
`CommandLine`	`match`	`Get-DomainManagedSecurityGroup`	1
`CommandLine`	`match`	`Find-DomainProcess`	1
`CommandLine`	`match`	`Get-WMIRegLastLoggedOn`	1
`CommandLine`	`match`	`Get-DomainComputer`	1
`CommandLine`	`match`	`Get-ForestGlobalCatalog`	1
`CommandLine`	`match`	`Get-DFSshare`	1
`OriginalFileName`	`eq`	`SharpView.exe`	1
`CommandLine`	`match`	`Get-NetRDPSession`	1
`CommandLine`	`match`	`Get-NetForest`	1
`CommandLine`	`match`	`Find-DomainShare`	1
`CommandLine`	`match`	`Get-NetProcess`	1

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Sigma 4 rules

HackTool - SharpView Execution severity high, 1 event, 84 indicators, 0 exclusions
System Network Connections Discovery Via Net.EXE severity low, 1 event, 8 indicators, 0 exclusions
Use Get-NetTCPConnection severity low, 1 event, 1 indicator, 0 exclusions
Use Get-NetTCPConnection - PowerShell Module severity low, 1 event, 1 indicator, 0 exclusions

Splunk 1 rule

GetNetTcpconnection with PowerShell Script Block 1 event, 2 indicators, 0 exclusions

Kusto Query Language 1 rule

Powershell Empire Cmdlets Executed in Command Line 1 event, 0 indicators, 0 exclusions

System Network Connections Discovery T1049