Query: detection rule: Detects the execution of certutil with either the "decode" or "decodehex" flags to decode base64 or hex encoded files. T
Matching passage: Sigma rule: Detects the execution of certutil with either the "decode" or "decodehex" flags to decode base64 or hex encoded files. T. Logsource: windows / process_creation. Rule: title: File Decoded From Base64/Hex Via Certutil.EXE id: cc9cbe82-7bc0-4ef5-bc23-bbfb83947be7 status: test description: Detects the execution of certutil with either the "decode" or "decodehex" flags to decode base64 or hex encoded files. This can be abused by attackers to decode an encoded payload before execution references: - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/certutil - https://unit42.paloaltonetworks.com/new-babyshark-malware-targets-u-s-national-security-think-tanks/ - https://news.sophos.com/en-us/2021/04/13/compromised-exchange-server-hosting-cryptojacker-targeting-other-exchange-servers/ - https://twitter.com/JohnLaTwC/status/835149808817991680 - https://learn.microsoft.com/en-us/archive/blogs/pki/basic-crl-checking-with-certutil - https://lolbas-project.github.io/lolbas/Binaries/Certutil/ author: Florian Roth (Nextron Systems), Jonhnathan Ribeiro, oscd.community date: 2023-02-15 modified: 2025-06-04 tags: - attack.stealth - attack.t1027 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: \certutil.exe - OriginalFileName: CertUtil.exe selection_cli: CommandLine|contains|windash: - '-decode ' - '-decodehex ' condition: all of selection_* falsepositives: - Unknown level: high regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_certutil_decode/info.yml
Near-miss passage: Sigma rule: Windows DCE-RPC functions which indicate an execution techniques on the remote system. All credit for the Zeek mapping o. Logsource: zeek / dce_rpc. Rule: title: MITRE BZAR Indicators for Execution id: b640c0b8-87f8-4daa-aef8-95a24261dd1d status: test description: Windows DCE-RPC functions which indicate an execution techniques on the remote system. All credit for the Zeek mapping of the suspicious endpoint/operation field goes to MITRE references: - https://github.com/mitre-attack/bzar#indicators-for-attck-execution author: '@neu5ron, SOC Prime' date: 2020-03-19 modified: 2021-11-27 tags: - attack.privilege-escalation - attack.persistence - attack.execution - attack.t1047 - attack.t1053.002 - attack.t1569.002 logsource: product: zeek service: dce_rpc detection: op1: endpoint: JobAdd operation: atsvc op2: endpoint: ITaskSchedulerService operation: SchRpcEnableTask op3: endpoint: ITaskSchedulerService operation: SchRpcRegisterTask op4: endpoint: ITaskSchedulerService operation: SchRpcRun op5: endpoint: IWbemServices operation: ExecMethod op6: endpoint: IWbemServices operation: ExecMethodAsync op7: endpoint: svcctl operation: CreateServiceA op8: endpoint: svcctl operation: CreateServiceW op9: endpoint: svcctl operation: StartServiceA op10: endpoint: svcctl operation: StartServiceW condition: 1 of op* falsepositives: - Windows administrator tasks or troubleshooting - Windows management scripts or software level: medium