Query: alert when 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: Detects suspicious processes based on name and location that access the windows credential manager and vault. Which can. Logsource: windows / file_access. Rule: title: Credential Manager Access By Uncommon Applications id: 407aecb1-e762-4acf-8c7b-d087bcff3bb6 status: test description: 'Detects suspicious processes based on name and location that access the windows credential manager and vault. Which can be a sign of credential stealing. Example case would be usage of mimikatz "dpapi::cred" function ' references: - https://hunter2.gitbook.io/darthsidious/privilege-escalation/mimikatz - https://www.absolomb.com/2018-01-26-Windows-Privilege-Escalation-Guide/ author: Nasreddine Bencherchali (Nextron Systems) date: 2022-10-11 modified: 2026-07-28 tags: - attack.t1003 - attack.credential-access logsource: category: file_access product: windows definition: 'Requirements: Microsoft-Windows-Kernel-File ETW provider' detection: selection: FileName|contains: - \AppData\Local\Microsoft\Credentials\ - \AppData\Roaming\Microsoft\Credentials\ - \AppData\Local\Microsoft\Vault\ - \ProgramData\Microsoft\Vault\ filter_main_system_folders: Image|startswith: - C:\Program Files\ - C:\Program Files (x86)\ - C:\Windows\system32\ - C:\Windows\SysWOW64\ filter_main_explorer: Image: C:\Windows\explorer.exe condition: selection and not 1 of filter_main_* falsepositives: - Legitimate software installed by the users for example in the "AppData" directory may access these files (for any reason). level: medium