Query: Sigma YAML for windows / process_creation
Matching passage: Sigma rule: Detects the use of curl with NTLM authentication and empty credentials (-u :), which can be abused to leak the currently. Logsource: windows / process_creation. Rule: title: NTLM Hash Leak Via Curl NTLM Authentication id: 916eb839-895e-47f8-99ee-3008bf377a3e status: test description: 'Detects the use of curl with NTLM authentication and empty credentials (-u :), which can be abused to leak the currently logged-in user''s NTLMv2 challenge-response to an attacker-controlled server, enabling offline cracking or relay attacks. When no credentials are provided, the Microsoft-shipped curl passes a NULL identity to Windows SSPI, which automatically falls back to the current user''s logon session credentials stored in LSASS — without requiring a plaintext password. This behavior is exclusive to the curl binary shipped by Microsoft (available since Windows 10 / Windows Server 2019), which is built with SSPI support. ' references: - https://github.com/curl/curl/blob/master/lib/vauth/ntlm_sspi.c#L128-L140 - https://learn.microsoft.com/en-us/windows/win32/secauthn/acquirecredentialshandle--ntlm - https://curl.se/docs/manpage.html#--ntlm author: Swachchhanda Shrawan Poudel (Nextron Systems) date: 2026-06-04 tags: - attack.credential-access - attack.t1187 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: \curl.exe - OriginalFileName: curl.exe selection_ntlm_flag: CommandLine|contains: --ntlm selection_empty_creds: CommandLine|re: '(?i)\s(-u|--user)\s*:' condition: all of selection_* falsepositives: - Should be very rare as it's not widely known or used, but could occur in legitimate use cases where curl is used with NTLM authentication and empty credentials, such as in certain scripts or automation tasks. level: high regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_curl_ntlm_hash_leak_attempt/info.yml
Near-miss passage: Sigma rule: Detects the execution of "forfiles" with the "/c" flag. While this is an expected behavior of the tool, it can be abused. Logsource: windows / process_creation. Rule: title: Forfiles Command Execution id: 9aa5106d-bce3-4b13-86df-3a20f1d5cf0b related: - id: a85cf4e3-56ee-4e79-adeb-789f8fb209a8 type: obsolete - id: fa47597e-90e9-41cd-ab72-c3b74cfb0d02 type: obsolete status: test description: 'Detects the execution of "forfiles" with the "/c" flag. While this is an expected behavior of the tool, it can be abused in order to proxy execution through it with any binary. Can be used to bypass application whitelisting. ' references: - https://lolbas-project.github.io/lolbas/Binaries/Forfiles/ - https://pentestlab.blog/2020/07/06/indirect-command-execution/ author: Tim Rauch, Elastic, E.M. Anhaus (originally from Atomic Blue Detections, Endgame), oscd.community date: 2022-06-14 modified: 2024-03-05 tags: - attack.execution - attack.t1059 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: \forfiles.exe - OriginalFileName: forfiles.exe selection_cli: CommandLine|contains|windash: ' -c ' condition: all of selection_* falsepositives: - Legitimate use via a batch script or by an administrator. level: medium