Hypervisor-protected Code Integrity (HVCI) Related Registry Tampering Via CommandLine

Status: experimental
Severity: high
Log source: product windows, category process_creation
Author: Swachchhanda Shrawan Poudel (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects the tampering of Hypervisor-protected Code Integrity (HVCI) related registry values via command line tool reg.exe. HVCI uses virtualization-based security to protect code integrity by ensuring that only trusted code can run in kernel mode. Adversaries may tamper with HVCI to load malicious or unsigned drivers, which can be used to escalate privileges, maintain persistence, or evade security mechanisms.

MITRE ATT&CK coverage

Tactic	Techniques
Defense Impairment	`T1685` Disable or Modify Tools

Event coverage

Provider	Event	Title
Sysmon	Event ID 1	Process creation

Rule body yaml

title: Hypervisor-protected Code Integrity (HVCI) Related Registry Tampering Via CommandLine
id: 6225c53a-a96e-4235-b28f-8d7997cd96eb
related:
    - id: 8b7273a4-ba5d-4d8a-b04f-11f2900d043a
      type: similar
status: experimental
description: |
    Detects the tampering of Hypervisor-protected Code Integrity (HVCI) related registry values via command line tool reg.exe.
    HVCI uses virtualization-based security to protect code integrity by ensuring that only trusted code can run in kernel mode.
    Adversaries may tamper with HVCI to load malicious or unsigned drivers, which can be used to escalate privileges, maintain persistence, or evade security mechanisms.
references:
    - https://www.sophos.com/en-us/blog/sharpening-the-knife-gold-blades-strategic-evolution
    - https://learn.microsoft.com/en-us/windows/security/hardware-security/enable-virtualization-based-protection-of-code-integrity
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2026-01-26
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\powershell.exe'
              - '\pwsh.exe'
              - '\reg.exe'
        - OriginalFileName:
              - 'PowerShell.EXE'
              - 'pwsh.dll'
              - 'reg.exe'
    selection_cli:
        CommandLine|contains:
            - 'add '
            - 'New-ItemProperty '
            - 'Set-ItemProperty '
            - 'si '  # SetItem Alias
    selection_cli_base:
        CommandLine|contains: '\DeviceGuard'
    selection_cli_key:
        CommandLine|contains:
            - 'EnableVirtualizationBasedSecurity'
            - 'HypervisorEnforcedCodeIntegrity'
    condition: all of selection_*
falsepositives:
    - Legitimate system administration tasks that require disabling HVCI for troubleshooting purposes when certain drivers or applications are incompatible with it.
level: high
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_hvci_registry_tampering/info.yml
simulation:
    - type: atomic-red-team
      name: Disable Hypervisor-Enforced Code Integrity (HVCI)
      technique: T1562.001
      atomic_guid: 70bd71e6-eba4-4e00-92f7-617911dbe020

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith:
          - '\powershell.exe'
          - '\pwsh.exe'
          - '\reg.exe'
    - OriginalFileName:
          - 'PowerShell.EXE'
          - 'pwsh.dll'
          - 'reg.exe'

Stage 2: `selection_cli`

selection_cli:
    CommandLine|contains:
        - 'add '
        - 'New-ItemProperty '
        - 'Set-ItemProperty '
        - 'si '

Stage 3: `selection_cli_base`

selection_cli_base:
    CommandLine|contains: '\DeviceGuard'

Stage 4: `selection_cli_key`

selection_cli_key:
    CommandLine|contains:
        - 'EnableVirtualizationBasedSecurity'
        - 'HypervisorEnforcedCodeIntegrity'

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	`EnableVirtualizationBasedSecurity` corpus 2 (sigma 2) `HypervisorEnforcedCodeIntegrity` `New-ItemProperty` corpus 3 (sigma 3) `Set-ItemProperty` corpus 3 (sigma 3) `\DeviceGuard` `add` corpus 12 (sigma 12) `si` corpus 5 (sigma 5)
`Image`	ends_with	`\powershell.exe` corpus 182 (sigma 182) `\pwsh.exe` corpus 168 (sigma 168) `\reg.exe` corpus 58 (sigma 58)
`OriginalFileName`	eq	`PowerShell.EXE` corpus 120 (sigma 84, splunk 30, elastic 6) `pwsh.dll` corpus 112 (sigma 79, splunk 30, elastic 3) `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)

Hypervisor-protected Code Integrity (HVCI) Related Registry Tampering Via CommandLine

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection_img`

Stage 2: `selection_cli`

Stage 3: `selection_cli_base`

Stage 4: `selection_cli_key`

Indicators

Keyboard shortcuts

Search operators

Hypervisor-protected Code Integrity (HVCI) Related Registry Tampering Via CommandLine

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection_img

Stage 2: selection_cli

Stage 3: selection_cli_base

Stage 4: selection_cli_key

Indicators

Stage 0: `condition`

Stage 1: `selection_img`

Stage 2: `selection_cli`

Stage 3: `selection_cli_base`

Stage 4: `selection_cli_key`