SEKOIA_Backdoor_Powershellempire_Csharp

rule SEKOIA_Backdoor_Powershellempire_Csharp : FILE
{
	meta:
		description = "Detects CSharp version of Empire"
		author = "Sekoia.io"
		id = "952e8e9b-8e4d-4550-9cf4-7ffd2f9d0672"
		date = "2022-04-15"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/backdoor_powershellempire_csharp.yar#L1-L23"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "536ef1167627c3dadb866d55e7eae2220c3fbd6961e2cfa71656656d984b9b90"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = "[-] Catastrophic .Net Agent Failure, Attempting Agent Restart:" ascii wide
		$ = "[!] Upload failed - No Delimiter" ascii wide
		$ = "SELECT * FROM Win32_IP4RouteTable" ascii wide
		$ = "no shell command supplied" ascii wide
		$ = "[-] CmdletInvocationException:" ascii wide
		$ = "[*] File download of" ascii wide
		$ = "Script successfully saved in memory" ascii wide
		$ = "Invoke-Empire" ascii wide
		$ = "website to reach:" ascii wide

	condition:
		uint16be( 0 ) == 0x4d5a and 5 of them and filesize < 1MB
}