ATT&CK coverage › Technique

Exfiltration Over Web Service: Exfiltration to Cloud Storage T1567.002

Adversaries may exfiltrate data to a cloud storage service rather than over their primary command and control channel. Cloud storage services allow for the storage, edit, and retrieval of data from a remote cloud storage server over the Internet.

Events covered

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

ProviderEvent IDTitle
Sysmon1Process creation
Sysmon3Network connection
Sysmon11FileCreate
Sysmon22DNSEvent (DNS query)
Security-Auditing4688A new process has been created.
DNS-Client3008DNS query is completed for the name QueryName, type QueryType, query options QueryOptions with status QueryStatus Results QueryResults.

Authoring guide

Patterns shared across the 12 rules above: which fields they filter on, what specific values they look for, and what they exclude. Field names are normalized 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 (7 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
QueryName6match 6.anonfiles.com, userstorage.mega.co.nz, ufile.io
DestinationHostname2ends_with 2mega.co.nz, mega.nz, api.dropboxapi.com, content.dropboxapi.com
Initiated2eq 2true
Image2ends_with 1, match 1\rclone.exe, \Dropbox
CommandLine2match 2multi-thread-streams, remote, --config , rest:http, sftp:
Description1eq 1Rsync for cloud storage
TargetFilename1match 1\.config\rclone\, :\Users\

Top indicator values (47 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.

FieldKindValueRules (here)Corpus reach
QueryNamematch.anonfiles.com22
QueryNamematchuserstorage.mega.co.nz22
QueryNamematchufile.io22
Initiatedeqtrue240
DestinationHostnameends_withmega.nz14
DestinationHostnameends_withmega.co.nz14
Imageends_with\rclone.exe1
CommandLinematchsync1
CommandLinematchauto-confirm1
CommandLinematch copy 14
CommandLinematchtransfers1
CommandLinematchno-check-certificate 1
CommandLinematchconfig18
CommandLinematchpcloud1
CommandLinematchmulti-thread-streams1
CommandLinematchlsd1
CommandLinematchls1
DescriptioneqRsync for cloud storage1
CommandLinematchremote1
CommandLinematchftp12

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 11 rules

Kusto Query Language 1 rule