Proxy T1090

Tactic: Command & Control

Adversaries may use a connection proxy to direct network traffic between systems or act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure. Many tools exist that enable traffic redirection through proxies or port redirection, including HTRAN, ZXProxy, and ZXPortMap. Adversaries use these types of proxies to manage command and control communications, reduce the number of simultaneous outbound network connections, provide resiliency in the face of connection loss, or to ride over existing trusted communications paths between victims to avoid suspicion. Adversaries may chain together multiple proxies to further disguise the source of malicious traffic.

Events covered

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

Authoring guide

These 88 rules share fields, values, and exclusions.

Fields filtered most (83 distinct)

These fields appear most often in rule filters.

FieldRulesHowSample values
CommandLine23contains 18, in 3, regex_match 3 tunnel , -config , run , *--config*, *authtoken*
process_name23eq 18, in 4, is_not_null 3, starts_with 2, contains 1curl, 3proxy, chisel, dnscat, proxychains
event.type18eq 18start, change
host.os.type18eq 17, in 1
Image16ends_with 15, contains 2\cloudflared.exe, \cloudflared-windows-386.exe, \cloudflared-windows-amd64.exe, \netsh.exe, :\program files (x86)\cloudflared\
process.args15eq 11, contains 5, wildcard 5, starts_with 4, in 3, regex_match 3--preproxy, --proxy, --socks5-hostname, -c, -o
EventType14in 9, eq 6exec, ProcessRollup2, exec_event, connection_attempted, connectionevent
QueryName7is_not_null 4, ends_with 3, wildcard 2, contains 1, in 1.hiddenservice.net, .onion, .onion.ca, *.2miners.com, *.4shared.com
DestinationHostname6contains 3, ends_with 3.localto.net, .localtonet.com, tunnel.ap.ngrok.com, tunnel.au.ngrok.com, tunnel.eu.ngrok.com
OriginalFileName6eq 6netsh.exe, cloudflared.exe, devtunnel.dll, plink, plink.exe
Hashes5contains 5sha256=0409c9b12f9d0eda86e461ed9bdabeefb00172b26322079681..., sha256=083150724b49604c8765c1ba19541fa260b133be0acb0647fc..., sha256=1293525a19cfe3bc8296b62fbfe19f083632ed644a1c18c10b..., md5=7d9c233b8c9e3f0ea290d2b84593c842, md5=9db2d314dd3f704a02051ef5ea210993
graph.metadata.entity_type4eq 4IP_ADDRESS, FILE
graph.metadata.product_name4eq 4GCTI Feed, Google Safe Browsing, VirusTotal Relationships
graph.metadata.source_type4eq 4GLOBAL_CONTEXT
graph.metadata.threat.threat_feed_name4eq 4Tor Exit Nodes, Benign Binaries

Top indicator values (904 distinct)

These values appear most often in rule predicates.

FieldKindValueRules (here)Corpus reach
event.typeeq
start
171078
EventTypein
ProcessRollup2
8117
EventTypein
exec
8201
EventTypein
exec_event
8149
EventTypein
start
8163
EventTypein
executed
598
EventTypein
process_started
583
EventTypeeq
exec
4576
graph.metadata.entity_typeeq
IP_ADDRESS
410
graph.metadata.entity_typeeq
FILE
317
graph.metadata.product_nameeq
GCTI Feed
48
graph.metadata.source_typeeq
GLOBAL_CONTEXT
420
graph.metadata.threat.threat_feed_nameeq
Tor Exit Nodes
47
parent_process_namein
bash
465
parent_process_namein
csh
439
parent_process_namein
dash
442
parent_process_namein
fish
440
parent_process_namein
ksh
440
parent_process_namein
sh
465
parent_process_namein
tcsh
440
parent_process_namein
zsh
463
CommandLinecontains
tunnel
33
CommandLinecontains
-config
33
CommandLinecontains
tunnel
36
Imageends_with
\cloudflared.exe
32
Initiatedeq
true
350
OriginalFileNameeq
netsh.exe
323
QueryNameends_with
.onion
33
graph.metadata.vendor_nameeq
Google Cloud Threat Intelligence
34
process.argseq
-s
38

Exclusions (181 distinct)

These values appear most often in top-level exclusions.

FieldKindValueRules excluding
CommandLinecontains
-blockdev
1
CommandLinecontains
-cdrom
1
CommandLinecontains
type=virt
1
CommandLinecontains
ansible
1
CurrentDirectorycontains
ansible
1
DestinationHostnamecontains
afdxtest.z01.azurefd.net
1
DestinationHostnamecontains
fp-afd.azurefd.net
1
DestinationHostnamecontains
fp-afdx-bpdee4gtg6frejfd.z01.azurefd.net
1
DestinationHostnamecontains
graph.azurefd.net
1
DestinationHostnamecontains
powershellinfraartifacts-gkhedzdeaghdezhr.z01.azurefd.net
1
DestinationHostnamecontains
roxy.azurefd.net
1
DestinationHostnamecontains
storage-explorer-publishing-feapcgfgbzc2cjek.b01.azurefd.net
1
FilterOrigineq
appcontainer loopback
1
Imagecontains
:\program files (x86)\cloudflared\
1
Imagecontains
:\program files\cloudflared\
1

Rules under this technique

These vendors publish rules tagged with this technique.

Platform (all)
Domain (all)

Sigma 34 rules

Elastic 22 rules

Splunk 14 rules

Kusto 10 rules

YARA-L 6 rules

Panther 2 rules