Direct Volume Access T1006

Tactic: Stealth

Adversaries may directly access a volume to bypass file access controls and file system monitoring. Windows allows programs to have direct access to logical volumes. Programs with direct access may read and write files directly from the drive by analyzing file system data structures. This technique may bypass Windows file access controls as well as file system monitoring tools.

Events covered

3 catalog events are tagged with this technique by at least one rule.

Authoring guide

Patterns shared across the 8 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (17 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

FieldRulesHowSample values
event.type6eq 5, in 1start, process_started
process.args6ne 3, eq 2, starts_with 2, contains 1, in 1-R, /dev/sd, /System/Volumes/Data, /bin/debugfs, mklink
process_name6eq 6, in 1debugfs, bash, busybox, cmd.exe, csh
host.os.type4eq 4
CommandLine3contains 2, starts_with 1/dev/sd, harddiskvolumeshadowcopy, ntds.dit
EventType3eq 3exec
OriginalFileName2eq 1, in 1cmd.exe, powershell.exe, wbadmin.exe
Device1contains 1floppy
Image1contains 1, ends_with 1, eq 1, is_null 1, starts_with 1\appdata\, \appdata\local\githubdesktop\app-, \appdata\local\keybase\upd.exe
ScriptBlockText1in 1invoke-ninjacopy, stealthclosefile, stealthclosefiledelegate
container.id1wildcard 1*
container.security_context.privileged1eq 1true
event.category1eq 1process
group.Ext.real.id1ne 10
process.entry_leader.entry_meta.type1eq 1container

Top indicator values (79 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.

FieldKindValueRules (here)Corpus reach
event.typeeq
start
5606
EventTypeeq
exec
3171
process.argsne
-R
33
process_nameeq
debugfs
33
process.argsstarts_with
/dev/sd
23
CommandLinecontains
harddiskvolumeshadowcopy
13
CommandLinecontains
ntds.dit
12
CommandLinestarts_with
/dev/sd
1
Devicecontains
floppy
1
Imagecontains
\appdata\
17
Imagecontains
\appdata\local\githubdesktop\app-
1
Imagecontains
\appdata\local\keybase\upd.exe
1
Imagecontains
\microsoft\
1
Imageends_with
\executables\ssdupdate.exe
1
Imageends_with
\hostmetadata\nvmehostmetadata.exe
1
Imageends_with
\mpdefendercoreservice.exe
1
Imageends_with
\msmpeng.exe
12
Imageends_with
\resources\app\git\mingw64\bin\git.exe
1
Imageends_with
\thor.exe
1
Imageeq
c:\windows\immersivecontrolpanel\systemsettings.exe
1
Imageeq
registry
1
Imageeq
system
13
Imagestarts_with
c:\$windows.~bt\
1
Imagestarts_with
c:\$winreagent\scratch\
1
Imagestarts_with
c:\program files (x86)\
1
Imagestarts_with
c:\program files\
1
Imagestarts_with
c:\programdata\microsoft\windows defender\platform\
1
Imagestarts_with
c:\users\
1
Imagestarts_with
c:\windows\ccm\
1
Imagestarts_with
c:\windows\explorer.exe
1

Exclusions (34 distinct)

Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.

FieldKindValueRules excluding
Devicecontains
floppy
1
Imagecontains
\appdata\
1
Imagecontains
\appdata\local\githubdesktop\app-
1
Imagecontains
\appdata\local\keybase\upd.exe
1
Imagecontains
\microsoft\
1
Imageends_with
\executables\ssdupdate.exe
1
Imageends_with
\hostmetadata\nvmehostmetadata.exe
1
Imageends_with
\mpdefendercoreservice.exe
1
Imageends_with
\msmpeng.exe
1
Imageends_with
\resources\app\git\mingw64\bin\git.exe
1
Imageends_with
\thor.exe
1
Imageeq
c:\windows\immersivecontrolpanel\systemsettings.exe
1
Imageeq
registry
1
Imageeq
system
1
Imagestarts_with
c:\$windows.~bt\
1

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Platform (all)
Domain (all)

Sigma 1 rule

Elastic 7 rules