Active Scanning T1595

Adversaries may execute active reconnaissance scans to gather information that can be used during targeting. Active scans are those where the adversary probes victim infrastructure via network traffic, as opposed to other forms of reconnaissance that do not involve direct interaction.

Events covered

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

Authoring guide

Patterns shared across the 6 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 (16 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
CommandLine4contains 3, in 1--healthcheck, --level full, --no-enum-limit, f , r
Image2ends_with 2\pingcastle.exe
OriginalFileName2eq 2pingcastle.exe
Product2eq 2Ping Castle
11eq 11
All_Traffic.app1contains 1\\
Computer1ne 1unknown
DestinationPort1lt 132000
Hashes1contains 1md5=011d967028e797a4c16d547f7ba1463f, md5=01bb2c16fadb992fa66228cd02d45c60, md5=049e85963826b059c9bac273bb9c82ab
ParentCommandLine1contains 1.bat, .chm, .cmd
description1ne 1false
dest_count1gt 110
port_count1gt 110
process_name1eq 1netspy.exe
sourcetype1eq 1XmlWinEventLog

Top indicator values (208 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
CommandLinecontains
--healthcheck
23
CommandLinecontains
--level full
23
CommandLinecontains
--no-enum-limit
23
CommandLinecontains
--scanner aclcheck
23
CommandLinecontains
--scanner antivirus
23
CommandLinecontains
--scanner computerversion
23
CommandLinecontains
--scanner foreignusers
23
CommandLinecontains
--scanner laps_bitlocker
23
CommandLinecontains
--scanner localadmin
23
CommandLinecontains
--scanner nullsession
23
CommandLinecontains
--scanner nullsession-trust
23
CommandLinecontains
--scanner oxidbindings
23
CommandLinecontains
--scanner remote
23
CommandLinecontains
--scanner share
23
CommandLinecontains
--scanner smb
23
CommandLinecontains
--scanner smb3querynetwork
23
CommandLinecontains
--scanner spooler
23
CommandLinecontains
--scanner startup
23
CommandLinecontains
--scanner zerologon
23
CommandLinecontains
--server
23
CommandLinecontains
f
1
CommandLinecontains
r
1
CommandLinecontains
s
1
CommandLinecontains
-i
12
CommandLinecontains
-i:
1
Imageends_with
\pingcastle.exe
23
OriginalFileNameeq
pingcastle.exe
23
Producteq
Ping Castle
22
1eq
1
16
All_Traffic.appcontains
\\
1

Exclusions (10 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
DestinationPortin
25
1
DestinationPortin
3268
1
DestinationPortin
389
1
DestinationPortin
443
1
DestinationPortin
53
1
DestinationPortin
5353
1
DestinationPortin
80
1
DestinationPortin
8080
1
DestinationPortin
8443
1
DestinationPortin
88
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.

Sigma 3 rules

Splunk 3 rules