false positives will occur based on grantedaccess 0x1010 and 0x1400, filter based on source image as needed or remove them. concern is cobalt strike usage of mimikatz will generate 0x1010 initially, but later be caught.

Techniques

Sample rules

Windows Possible Credential Dumping

source: splunk
technicques:
- T1003.001
- T1003

Description

The following analytic detects potential credential dumping by identifying specific GrantedAccess permission requests and CallTrace DLLs targeting the LSASS process. It leverages Sysmon EventCode 10 logs, focusing on access requests to lsass.exe and call traces involving debug and native API DLLs like dbgcore.dll, dbghelp.dll, and ntdll.dll. This activity is significant as credential dumping can lead to unauthorized access to sensitive credentials. If confirmed malicious, attackers could gain elevated privileges and persist within the environment, posing a severe security risk.

Detection logic

`sysmon` EventCode=10 TargetImage=*\\lsass.exe granted_access IN ("0x01000", "0x1010", "0x1038", "0x40", "0x1400", "0x1fffff", "0x1410", "0x143a", "0x1438", "0x1000") CallTrace IN ("*dbgcore.dll*", "*dbghelp.dll*", "*ntdll.dll*", "*kernelbase.dll*", "*kernel32.dll*") NOT SourceUser IN ("NT AUTHORITY\\SYSTEM", "NT AUTHORITY\\NETWORK SERVICE") 
| stats count min(_time) as firstTime max(_time) as lastTime by dest, SourceImage, GrantedAccess, TargetImage, SourceProcessId, SourceUser, TargetUser 
| rename SourceUser as user 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `windows_possible_credential_dumping_filter`