Active Scanning T1595

Tactic: Reconnaissance

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

These 73 rules share fields, values, and exclusions.

Fields filtered most (122 distinct)

These fields appear most often in rule filters.

FieldRulesHowSample values
EventType12eq 5, in 4, contains 3exec, flow_started, network_flow, connectionevent, vcn.flowlogs
data_data_result_s10eq 10failed
data_data_severity_s10eq 10High
deviceProduct_s10eq 10azure
sourcetype10eq 9, in 1cisco:sfw:estreamer, cisco:sdwan:syslog, cisco:cloud_security:proxy, cisco:sdwan:access, nginx:plus:access
type10eq 10Microsoft.Compute/disks, Microsoft.Compute/virtualMachines, Microsoft.ContainerRegistry/registries, Microsoft.KeyVault/vaults, Microsoft.Network/networkSecurityGroups
DestinationPort7is_not_null 3, in 2, eq 1, lt 110000, 1025, 1026, 139, 21
src_ip7is_not_null 5, in 2, cidr_match 110.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16
CommandLine4contains 3, in 1--healthcheck, --level full, --no-enum-limit, f , r
Esql.event_count4gt 3, lt 150, 5, 500
dest_ip4cidr_match 2, in 1, is_not_null 110.0.0.0/8, 127.0.0.0/8, 169.254.0.0/16, 172.16.0.0/12, 192.168.0.0/16
http.response.status_code4eq 2, in 2200, 403, 404, 500, 502
process_name4in 3, eq 1bash, binwalk, busybox, cewl, commix
Message3contains 2, eq 1UserSignIn, found user-agent associated with security scanner, unauthorized access attempt
data_stream.dataset3eq 3gcp.audit, network_traffic.http, network_traffic.icmp

Top indicator values (749 distinct)

These values appear most often in rule predicates.

FieldKindValueRules (here)Corpus reach
data_data_result_seq
failed
1010
data_data_severity_seq
High
1010
deviceProduct_seq
azure
1010
EventTypein
flow_started
33
EventTypein
network_flow
33
event.typeeq
start
31078
sourcetypeeq
cisco:sfw:estreamer
332
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
DestinationPortin
139
26
DestinationPortin
21
23
DestinationPortin
22
25

Exclusions (55 distinct)

These values appear most often in top-level exclusions.

FieldKindValueRules excluding
DestinationPortin
443
2
DestinationPortin
80
2
DestinationPortin
25
1
process.argswildcard
-*z*
2
process.argswildcard
127.0.0.1
2
process.argswildcard
localhost
2
process_namein
nc
2
process_namein
nc.traditional
2
process_namein
ncat
2
process_namein
netcat
2
src_ipcidr_match
10.0.0.0/8
2
src_ipcidr_match
127.0.0.0/8
2
src_ipcidr_match
169.254.0.0/16
2
src_ipcidr_match
172.16.0.0/12
2
src_ipcidr_match
192.168.0.0/16
2

Rules under this technique

These vendors publish rules tagged with this technique.

Platform (all)
Domain (all)

Sigma 5 rules

Elastic 20 rules

Splunk 13 rules

Kusto 27 rules

Panther 8 rules