csi.exe

Use csi.exe to run unsigned C# code.

Use Local execution of unsigned C# code.

csi.exe {PATH:.cs}

Evidence

Upstream reference

Environment

Local host

Context

user

Native

Execute

MITRE

T1127

Detection

Sigma: github.com/SigmaHQ/sigma/blob/c04bef2fbbe8beff6c7620d5d7ea6872dbe7acba/rules/windows/process_creation/proc_creation_win_csi_execution.yml

Sigma: github.com/SigmaHQ/sigma/blob/683b63f8184b93c9564c4310d10c571cbe367e1e/rules/windows/process_creation/proc_creation_win_csi_use_of_csharp_console.yml

Elastic: github.com/elastic/detection-rules/blob/414d32027632a49fb239abb8fbbb55d3fa8dd861/rules/windows/defense_evasion_unusual_process_network_connection.toml

Elastic: github.com/elastic/detection-rules/blob/414d32027632a49fb239abb8fbbb55d3fa8dd861/rules/windows/defense_evasion_network_connection_from_windows_binary.toml

BlockRule: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules

Refs

twitter.com/subTee/status/781208810723549188

enigma0x3.net/2016/11/17/bypassing-application-whitelisting-by-using-dnx-exe/

lolbas-project.github.io/lolbas/OtherMSBinaries/csi/