ATT&CK coverage › Technique
Exfiltration Over Web Service T1567
Adversaries may use an existing, legitimate external Web service to exfiltrate data rather than their primary command and control channel. Popular Web services acting as an exfiltration mechanism may give a significant amount of cover due to the likelihood that hosts within a network are already communicating with them prior to compromise. Firewall rules may also already exist to permit traffic to these services.
Events covered
2 catalog events are tagged with this technique by at least one rule.
| Provider | Event ID | Title |
|---|---|---|
| Sysmon | 1 | Process creation |
| Sysmon | 3 | Network connection |
Authoring guide
Patterns shared across the 9 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 (6 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.
Top indicator values (111 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.
Common exclusions (23 distinct)
Field/operator/value combinations that rules under this technique routinely exclude (top-level not() clauses). 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.
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 8 rules
- Arbitrary File Download Via ConfigSecurityPolicy.EXE
- Communication To Ngrok Tunneling Service Initiated
- LOLBAS Data Exfiltration by DataSvcUtil.exe
- Network Connection Initiated To BTunnels Domains
- Network Connection Initiated To Cloudflared Tunnels Domains
- Network Connection Initiated To Visual Studio Code Tunnels Domain
- Process Initiated Network Connection To Ngrok Domain
- Suspicious Non-Browser Network Communication With Telegram API