Dumping of Sensitive Hives Via Reg.EXE

Status: test
Severity: high
Log source: product windows, category process_creation
Author: Teymur Kheirkhabarov, Endgame, JHasenbusch, Daniil Yugoslavskiy, oscd.community, frack113
Source: github.com/SigmaHQ/sigma

Detects the usage of "reg.exe" in order to dump sensitive registry hives. This includes SAM, SYSTEM and SECURITY hives.

MITRE ATT&CK coverage

Tactic	Techniques
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
Sysmon	Event ID 1	Process creation

Rule body yaml

title: Dumping of Sensitive Hives Via Reg.EXE
id: fd877b94-9bb5-4191-bb25-d79cbd93c167
related:
    - id: 038cd51c-3ad8-41c5-ba8f-5d1c92f3cc1e
      type: obsolete
    - id: 4d6c9da1-318b-4edf-bcea-b6c93fa98fd0
      type: obsolete
status: test
description: Detects the usage of "reg.exe" in order to dump sensitive registry hives. This includes SAM, SYSTEM and SECURITY hives.
references:
    - https://www.slideshare.net/heirhabarov/hunting-for-credentials-dumping-in-windows-environment
    - https://eqllib.readthedocs.io/en/latest/analytics/aed95fc6-5e3f-49dc-8b35-06508613f979.html
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1003/T1003.md
    - https://www.wietzebeukema.nl/blog/windows-command-line-obfuscation
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1003.002/T1003.002.md#atomic-test-1---registry-dump-of-sam-creds-and-secrets
author: Teymur Kheirkhabarov, Endgame, JHasenbusch, Daniil Yugoslavskiy, oscd.community, frack113
date: 2019-10-22
modified: 2023-12-13
tags:
    - attack.credential-access
    - attack.t1003.002
    - attack.t1003.004
    - attack.t1003.005
    - car.2013-07-001
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\reg.exe'
        - OriginalFileName: 'reg.exe'
    selection_cli_flag:
        CommandLine|contains:
            - ' save '
            - ' export '
            - ' ˢave '
            - ' eˣport '
    selection_cli_hklm:
        CommandLine|contains:
            - 'hklm'
            - 'hk˪m'
            - 'hkey_local_machine'
            - 'hkey_˪ocal_machine'
            - 'hkey_loca˪_machine'
            - 'hkey_˪oca˪_machine'
    selection_cli_hive:
        CommandLine|contains:
            - '\system'
            - '\sam'
            - '\security'
            - '\ˢystem'
            - '\syˢtem'
            - '\ˢyˢtem'
            - '\ˢam'
            - '\ˢecurity'
    condition: all of selection_*
falsepositives:
    - Dumping hives for legitimate purpouse i.e. backup or forensic investigation
level: high

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith: '\reg.exe'
    - OriginalFileName: 'reg.exe'

Stage 2: `selection_cli_flag`

selection_cli_flag:
    CommandLine|contains:
        - ' save '
        - ' export '
        - ' ˢave '
        - ' eˣport '

Stage 3: `selection_cli_hklm`

selection_cli_hklm:
    CommandLine|contains:
        - 'hklm'
        - 'hk˪m'
        - 'hkey_local_machine'
        - 'hkey_˪ocal_machine'
        - 'hkey_loca˪_machine'
        - 'hkey_˪oca˪_machine'

Stage 4: `selection_cli_hive`

selection_cli_hive:
    CommandLine|contains:
        - '\system'
        - '\sam'
        - '\security'
        - '\ˢystem'
        - '\syˢtem'
        - '\ˢyˢtem'
        - '\ˢam'
        - '\ˢecurity'

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
`CommandLine`	match	`export` corpus 3 (sigma 3) `eˣport` `save` `ˢave` `\sam` `\security` `\system` `\syˢtem` `\ˢam` `\ˢecurity` `\ˢystem` `\ˢyˢtem` `hkey_local_machine` corpus 2 (sigma 2) `hkey_loca˪_machine` `hkey_˪ocal_machine` `hkey_˪oca˪_machine` `hklm` corpus 4 (sigma 3, kusto 1) `hk˪m`
`Image`	ends_with	`\reg.exe` corpus 58 (sigma 58)
`OriginalFileName`	eq	`reg.exe` corpus 42 (sigma 32, splunk 8, elastic 2)

`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)

Dumping of Sensitive Hives Via Reg.EXE

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection_img`

Stage 2: `selection_cli_flag`

Stage 3: `selection_cli_hklm`

Stage 4: `selection_cli_hive`

Indicators

Keyboard shortcuts

Search operators

Dumping of Sensitive Hives Via Reg.EXE

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection_img

Stage 2: selection_cli_flag

Stage 3: selection_cli_hklm

Stage 4: selection_cli_hive

Indicators

Stage 0: `condition`

Stage 1: `selection_img`

Stage 2: `selection_cli_flag`

Stage 3: `selection_cli_hklm`

Stage 4: `selection_cli_hive`