Query: alert when Detects attackers using tooling with bad opsec defaults. E.g. spawning a sacrificial process to inject a capability into
Matching passage: Sigma rule: Detects attackers using tooling with bad opsec defaults. E.g. spawning a sacrificial process to inject a capability into. Logsource: windows / process_creation. Rule: title: Bad Opsec Defaults Sacrificial Processes With Improper Arguments id: a7c3d773-caef-227e-a7e7-c2f13c622329 related: - id: f5647edc-a7bf-4737-ab50-ef8c60dc3add type: obsolete status: test description: 'Detects attackers using tooling with bad opsec defaults. E.g. spawning a sacrificial process to inject a capability into the process without taking into account how the process is normally run. One trivial example of this is using rundll32.exe without arguments as a sacrificial process (default in CS, now highlighted by c2lint), running WerFault without arguments (Kraken - credit am0nsec), and other examples. ' references: - https://blog.malwarebytes.com/malwarebytes-news/2020/10/kraken-attack-abuses-wer-service/ - https://www.cobaltstrike.com/help-opsec - https://twitter.com/CyberRaiju/status/1251492025678983169 - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/regsvr32 - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/rundll32 - https://learn.microsoft.com/en-us/dotnet/framework/tools/regasm-exe-assembly-registration-tool - https://learn.microsoft.com/en-us/dotnet/framework/tools/regsvcs-exe-net-services-installation-tool author: Oleg Kolesnikov @securonix invrep_de, oscd.community, Florian Roth (Nextron Systems), Christian Burkard (Nextron Systems) date: 2020-10-23 modified: 2024-08-15 tags: - attack.stealth - attack.t1218.011 logsource: category: process_creation product: windows detection: selection_werfault: Image|endswith: \WerFault.exe CommandLine|endswith: WerFault.exe selection_rundll32: Image|endswith: \rundll32.exe CommandLine|endswith: rundll32.exe selection_regsvcs: Image|endswith: \regsvcs.exe CommandLine|endswith: regsvcs.exe selection_regasm: Image|endswith: \regasm.exe CommandLine|endswith: regasm.exe selection_regsvr32: Image|endswith: \regsvr32.exe CommandLine|endswith: regsvr32.exe filter_optional_edge_update: ParentImage|contains: \AppData\Local\Microsoft\EdgeUpdate\Install\{ Image|endswith: \rundll32.exe CommandLine|endswith: rundll32.exe filter_optional_chromium_installer: ParentImage|contains: - \AppData\Local\BraveSoftware\Brave-Browser\Application\ - \AppData\Local\Google\Chrome\Application\ ParentImage|endswith: \Installer\setup.exe ParentCommandLine|contains: '--uninstall ' Image|endswith: \rundll32.exe CommandLine|endswith: rundll32.exe condition: 1 of selection_* and not 1 of filter_optional_* falsepositives: - Unlikely level: high
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