Detection rules › Splunk

Mimikatz (Sysmon)

Group by
_time, host
Source
github.com/anvilogic-forge/armory

Mimikatz is used to extract plaintexts passwords, hash, PIN code and Kerberos tickets from memory. Mimikatz can also perform pass-the-hash, pass-the-ticket or build Golden tickets

MITRE ATT&CK coverage

References

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation
SysmonEvent ID 10ProcessAccess

Rule body yaml

id: '1033.1041'
title: Mimikatz
description: 'Mimikatz is used to extract plaintexts passwords, hash, PIN code and
  Kerberos tickets from memory. Mimikatz can also perform pass-the-hash, pass-the-ticket
  or build Golden tickets. -- Threat Actor Association: APT10/Cicada, APT27/Emissary
  Panda, APT29/Nobelium, APT41/Wicked Panda, Carbanak, DarkSide, BlackMatter, FamousSparrow,
  FIN7, FIN12, Hello Kitty / Five Hands, Karakurt, Lapsus$, LockBit, Memento Team,
  TRACER KITTEN, TRAVELING SPIDER, SILENCE, UNC2596, Witchetty -- Software Association:
  Blackcat/ALPHV, Conti, Cuba, Midas, Lockbit, LV, Nefilim, Play, Qakbot, Revil, SamSam,
  Stonefly, WASTEDLOCKER -- Atomics T1003.001 Test #6 Atomics T1003.001 Test #10 Atomics
  T1550.002 Test#1'
logic_format: Splunk
logic: ' `get_endpoint_data` `get_endpoint_data_sysmon` (EventCode=1 AND ( "mimikatz"
  OR "gentilkiwi" OR "whoami" OR "IntegriyLevel=High" )) OR (EventCode=10 AND ("lsass.exe"
  OR mimikatz)) | table _time, host, user dest, direction, dvc, dvc_nt_host, event_id,
  eventtype, hashes, host, index, parent_process, parent_process_id, parent_process_name,
  parent_process_path, process, process_current_directory, process_id, process_name,
  process_path, signature_id, source, sourcetype, tag, user, user_id | bin span=60s
  | stats values(*) as * by _time, host | where (match(parent_process_name,"(?i)(powershell.exe)|(cmd.exe)")
  AND match(parameters,"(?i)gentilkiwi") OR match(process,"(?i)mimikatz")) OR (match(parameters,"(?i)granted_access=0x1010")
  AND match(parent_process_name,"(?i)(powershell.exe)|(cmd.exe)") AND match(process_path,"(?i).lsass.exe")
  AND match(process,"(?i)KERNELBASE.dll") AND match(process,"(?i)ntdll.dll") AND match(process,"(?i)whoami"))
  | bin span=300s _time | stats values(*) as * by _time, host '
techniques:
- credential-access:os credential dumping:lsass memory
- credential-access:os credential dumping:security account manager
- credential-access:os credential dumping:dcsync
- credential-access:os credential dumping:lsa secrets
- credential-access:steal or forge kerberos tickets:golden ticket
- credential-access:steal or forge kerberos tickets:silver ticket
- credential-access:unsecured credentials:credentials in registry
technique_id:
- T1552.002
- T1003.006
- T1003.004
- T1003.002
- T1558.002
- T1558.001
- T1003.001
data_category:
- Windows Sysmon
references:
- https://www.sans.org/reading-room/whitepapers/detection/mimikatz-overview-defenses-detection-36780

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_sysmon` (EventCode=1 AND ( "mimikatz" OR "gentilkiwi" OR "whoami" OR "IntegriyLevel=High" )) OR (EventCode=10 AND ("lsass.exe" OR mimikatz))

Stage 2: table

| table _time, host, user dest, direction, dvc, dvc_nt_host, event_id, eventtype, hashes, host, index, parent_process, parent_process_id, parent_process_name, parent_process_path, process, process_current_directory, process_id, process_name, process_path, signature_id, source, sourcetype, tag, user, user_id

Stage 3: bucket

| bin span=60s

Stage 4: stats

| stats values(*) as * by _time, host

Stage 5: where

| where (match(parent_process_name,"(?i)(powershell.exe)|(cmd.exe)") AND match(parameters,"(?i)gentilkiwi") OR match(process,"(?i)mimikatz")) OR (match(parameters,"(?i)granted_access=0x1010") AND match(parent_process_name,"(?i)(powershell.exe)|(cmd.exe)") AND match(process_path,"(?i).lsass.exe") AND match(process,"(?i)KERNELBASE.dll") AND match(process,"(?i)ntdll.dll") AND match(process,"(?i)whoami"))

Stage 6: bucket

| bin span=300s _time

Stage 7: stats

| stats values(*) as * by _time, host

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventCodeeq
  • 1 corpus 237 (splunk 224, kusto 13)
  • 10 corpus 16 (splunk 15, kusto 1)
parametersmatch
  • "(?i)gentilkiwi"
  • "(?i)granted_access=0x1010"
parent_process_namematch
  • "(?i)(powershell.exe)|(cmd.exe)"
processmatch
  • "(?i)KERNELBASE.dll"
  • "(?i)mimikatz"
  • "(?i)ntdll.dll"
  • "(?i)whoami"
process_pathmatch
  • "(?i).lsass.exe"

Search terms

Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.

StageTerm
1"mimikatz"
1"gentilkiwi"
1"whoami"
1"IntegriyLevel=High"
1"lsass.exe"
1mimikatz