Backdoor introduction via registry permission change through WMI (DAMP)

Status: experimental
Severity: high
Time window: 5m
Log source: product windows, service security
Author: mdecrevoisier
Source: github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker modifies registry permissions on a local or remote target in order to introduce a backdoor and dump hashes and credentials.

MITRE ATT&CK coverage

Tactic	Techniques
Persistence	`T1112` Modify Registry
Defense Impairment	`T1112` Modify Registry
Credential Access	`T1003.002` OS Credential Dumping: Security Account Manager, `T1003.004` OS Credential Dumping: LSA Secrets, `T1003.005` OS Credential Dumping: Cached Domain Credentials

Event coverage

Provider	Event	Title
Security-Auditing	Event ID 4674	An operation was attempted on a privileged object.

Rule body yaml

title: Backdoor introduction via registry permission change through WMI (DAMP)
description: Detects scenarios where an attacker modifies registry permissions on a local or remote target in order to introduce a backdoor and dump hashes and credentials.
correlation: correlate TargetLogonId from ID 4624 with SubjectLogonId from ID 4674 to identify the source of the change.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0005-Defense%20Evasion/T1112-Modify%20registry
- https://github.com/HarmJ0y/DAMP
- https://threathunterplaybook.com/notebooks/windows/07_discovery/WIN-190625024610.html
- http://www.harmj0y.net/blog/activedirectory/remote-hash-extraction-on-demand-via-host-security-descriptor-modification/
- https://github.com/mitre/microsoft-windows-2012r2-memberserver-stig-baseline/blob/master/controls/V-1152.rb
- https://www.darkoperator.com/blog/2017/10/14/basics-of-tracking-wmi-activity
tags:
- attack.defense_evasion
- attack.t1112
- attack.credential_access
- attack.t1003.002 # SAM
- attack.t1003.004 # LSA Secrets
- attack.t1003.005 # Cached Domain Credentials
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4674
    ProcessName|endswith: '\System32\wbem\WmiPrvSE.exe'
    ObjectServer: Security
    ObjectType: Key
    ObjectName|startswith:
      - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\SecurePipeServers\winreg' # controls access to remote registry
      - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\Data'  # required to calculate SysKey/bootkey
      - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\GBG'   # required to calculate SysKey/bootkey
      - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\JD'    # required to calculate SysKey/bootkey
      - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\Skew1' # required to calculate SysKey/bootkey
      - '\REGISTRY\MACHINE\SECURITY\Policy\Accounts'
      - '\REGISTRY\MACHINE\SECURITY\Policy\Pol'
      - '\REGISTRY\MACHINE\SECURITY\Policy\Secrets'   # contains the encrypted machine account hash in \SECURITY\Policy\Secrets\$MACHINE.ACC\CurrVal
      - '\REGISTRY\MACHINE\SECURITY\Policy\PolEKList' # contains the encrypted LSA key
      - '\REGISTRY\MACHINE\SECURITY\Cache'            # Contains domain cached credentials
      - '\REGISTRY\MACHINE\SAM\SAM\DOMAINS\Account'   # contains local user hashes
      - '\REGISTRY\MACHINE\SAM\SAM\DOMAINS\Builtin'
  filter:
    SubjectUserName|endswith: $
  condition: selection and not filter | count(ObjectName) by Computer > 10
  timeframe: 5m
falsepositives:
- None
level: high

Stages and Predicates

Stage 0: `condition`

selection and not filter | count(ObjectName) by Computer > 10

Stage 1: `selection`

selection:
  EventID: 4674
  ProcessName|endswith: '\System32\wbem\WmiPrvSE.exe'
  ObjectServer: Security
  ObjectType: Key
  ObjectName|startswith:
    - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\SecurePipeServers\winreg'
    - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\Data'
    - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\GBG'
    - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\JD'
    - '\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\Skew1'
    - '\REGISTRY\MACHINE\SECURITY\Policy\Accounts'
    - '\REGISTRY\MACHINE\SECURITY\Policy\Pol'
    - '\REGISTRY\MACHINE\SECURITY\Policy\Secrets'
    - '\REGISTRY\MACHINE\SECURITY\Policy\PolEKList'
    - '\REGISTRY\MACHINE\SECURITY\Cache'
    - '\REGISTRY\MACHINE\SAM\SAM\DOMAINS\Account'
    - '\REGISTRY\MACHINE\SAM\SAM\DOMAINS\Builtin'

Threshold: > 10

Stage 2: `not filter`

filter:
  SubjectUserName|endswith: $

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

Field	Kind	Excluded values
`SubjectUserName`	ends_with	`$`

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.

Field	Kind	Values
`ObjectName`	starts_with	`\REGISTRY\MACHINE\SAM\SAM\DOMAINS\Account` `\REGISTRY\MACHINE\SAM\SAM\DOMAINS\Builtin` `\REGISTRY\MACHINE\SECURITY\Cache` `\REGISTRY\MACHINE\SECURITY\Policy\Accounts` `\REGISTRY\MACHINE\SECURITY\Policy\Pol` `\REGISTRY\MACHINE\SECURITY\Policy\PolEKList` `\REGISTRY\MACHINE\SECURITY\Policy\Secrets` `\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\Data` `\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\GBG` `\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\JD` `\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\Lsa\Skew1` `\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\SecurePipeServers\winreg`
`ObjectServer`	eq	`Security` corpus 5 (sigma 5)
`ObjectType`	eq	`Key` corpus 8 (sigma 4, kusto 4)
`ProcessName`	ends_with	`\System32\wbem\WmiPrvSE.exe`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

Backdoor introduction via registry permission change through WMI (DAMP)

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection`

Stage 2: `not filter`

Exclusions

Indicators

Keyboard shortcuts

Search operators

Backdoor introduction via registry permission change through WMI (DAMP)

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection

Stage 2: not filter

Exclusions

Indicators

Stage 0: `condition`

Stage 1: `selection`

Stage 2: `not filter`