Query: detect Detects execution of "csc.exe" to compile .NET code. Attackers often leverage this to compile code on the fly and use it in logs
Matching passage: Sigma rule: Detects execution of "csc.exe" to compile .NET code. Attackers often leverage this to compile code on the fly and use it. Logsource: windows / process_creation. Rule: title: Dynamic .NET Compilation Via Csc.EXE id: dcaa3f04-70c3-427a-80b4-b870d73c94c4 status: test description: Detects execution of "csc.exe" to compile .NET code. Attackers often leverage this to compile code on the fly and use it in other stages. references: - https://securityboulevard.com/2019/08/agent-tesla-evading-edr-by-removing-api-hooks/ - https://www.clearskysec.com/wp-content/uploads/2018/11/MuddyWater-Operations-in-Lebanon-and-Oman.pdf - https://app.any.run/tasks/c6993447-d1d8-414e-b856-675325e5aa09/ - https://twitter.com/gN3mes1s/status/1206874118282448897 - https://github.com/redcanaryco/atomic-red-team/blob/b27a3cb25025161d49ac861cb216db68c46a3537/atomics/T1027.004/T1027.004.md#atomic-test-1---compile-after-delivery-using-cscexe author: Florian Roth (Nextron Systems), X__Junior (Nextron Systems) date: 2019-08-24 modified: 2026-03-23 tags: - attack.stealth - attack.t1027.004 logsource: category: process_creation product: windows detection: selection_img: Image|endswith: \csc.exe selection_susp_location_1: CommandLine|contains: - :\Perflogs\ - :\Users\Public\ - \AppData\Local\Temp\ - \Temporary Internet - \Windows\Temp\ selection_susp_location_2: - CommandLine|contains|all: - :\Users\ - \Favorites\ - CommandLine|contains|all: - :\Users\ - \Favourites\ - CommandLine|contains|all: - :\Users\ - \Contacts\ - CommandLine|contains|all: - :\Users\ - \Pictures\ selection_susp_location_3: CommandLine|re: (?:[Pp]rogram[Dd]ata|%(?:[Ll]ocal)?[Aa]pp[Dd]ata%|\\[Aa]pp[Dd]ata\\(?:[Ll]ocal(?:[Ll]ow)?|[Rr]oaming))\\[^\\]{1,256}$ filter_main_programfiles: ParentImage|startswith: - C:\Program Files (x86)\ - C:\Program Files\ filter_main_sdiagnhost: ParentImage: C:\Windows\System32\sdiagnhost.exe filter_main_w3p: ParentImage: C:\Windows\System32\inetsrv\w3wp.exe filter_optional_chocolatey: ParentImage: - C:\ProgramData\chocolatey\choco.exe - C:\ProgramData\chocolatey\tools\shimgen.exe filter_optional_defender: ParentCommandLine|contains: \ProgramData\Microsoft\Windows Defender Advanced Threat Protection filter_optional_ansible: ParentCommandLine|contains: - JwB7ACIAZgBhAGkAbABlAGQAIgA6AHQAcgB1AGUALAAiAG0AcwBnACIAOgAiAEEAbgBzAGkAYgBsAGUAIAByAGUAcQB1AGkAcgBlAHMAIABQAG8AdwBlAHIAUwBoAGUAbABsACAAdgAzAC4AMAAgAG8AcgAgAG4AZQB3AGUAcgAiAH0AJw - cAewAiAGYAYQBpAGwAZQBkACIAOgB0AHIAdQBlACwAIgBtAHMAZwAiADoAIgBBAG4AcwBpAGIAbABlACAAcgBlAHEAdQBpAHIAZQBzACAAUABvAHcAZQByAFMAaABlAGwAbAAgAHYAMwAuADAAIABvAHIAIABuAGUAdwBlAHIAIgB9ACcA - nAHsAIgBmAGEAaQBsAGUAZAAiADoAdAByAHUAZQAsACIAbQBzAGcA
Near-miss passage: Sigma rule: Detect suspicious Kerberos TGT requests. Once an attacer obtains a computer certificate by abusing Active Directory Cert. Logsource: windows / security. Rule: title: PetitPotam Suspicious Kerberos TGT Request id: 6a53d871-682d-40b6-83e0-b7c1a6c4e3a5 status: test description: 'Detect suspicious Kerberos TGT requests. Once an attacer obtains a computer certificate by abusing Active Directory Certificate Services in combination with PetitPotam, the next step would be to leverage the certificate for malicious purposes. One way of doing this is to request a Kerberos Ticket Granting Ticket using a tool like Rubeus. This request will generate a 4768 event with some unusual fields depending on the environment. This analytic will require tuning, we recommend filtering Account_Name to the Domain Controller computer accounts. ' references: - https://github.com/topotam/PetitPotam - https://isc.sans.edu/forums/diary/Active+Directory+Certificate+Services+ADCS+PKI+domain+admin+vulnerability/27668/ - https://github.com/splunk/security_content/blob/88d689fe8a055d8284337b9fad5d9152b42043db/detections/endpoint/petitpotam_suspicious_kerberos_tgt_request.yml author: Mauricio Velazco, Michael Haag date: 2021-09-02 modified: 2022-10-05 tags: - attack.credential-access - attack.t1187 logsource: product: windows service: security definition: The advanced audit policy setting "Account Logon > Kerberos Authentication Service" must be configured for Success/Failure detection: selection: EventID: 4768 TargetUserName|endswith: $ CertThumbprint|contains: '*' filter_local: IpAddress: ::1 filter_thumbprint: CertThumbprint: '' condition: selection and not 1 of filter_* falsepositives: - False positives are possible if the environment is using certificates for authentication. We recommend filtering Account_Name to the Domain Controller computer accounts. level: high