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ATT&CK Technique

Domain Fronting

T1172 · command-and-control
▤ Generate a SIEM detection for T1172 ◈ Vendor-native detections for T1172 ⚠ CVEs mapped to T1172 ♛ Hunt package for T1172 ◎ Check your coverage for T1172

Domain fronting takes advantage of routing schemes in Content Delivery Networks (CDNs) and other services which host multiple domains to obfuscate the intended destination of HTTPS traffic or traffic tunneled through HTTPS. The technique involves using different domain names in the SNI field of the TLS header and the Host field of the HTTP header. If both domains are served from the same CDN, then the CDN may route to the address specified in the HTTP header after unwrapping the TLS header. A variation of the technique, "domainless" fronting, utilizes a SNI field that is left blank.

this may allow the fronting to work even when the CDN attempts to validate that the SNI and HTTP Host fields match (if the blank SNI fields are ignored). For example, if domain-x and domain-y are customers of the same CDN, it is possible to place domain-x in the TLS header and domain-y in the HTTP header. Traffic will appear to be going to domain-x, however the CDN may route it to domain-y.

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How to use this page - the detection-engineering loop
Attackers have goals (tactics - “get credentials”, “move laterally”) and techniques are the concrete methods they use to reach them. This page is one method - T1172 - broken into everything you need to catch it.
The loop this page is built for (this is the job):
  1. Understand the behaviour - read the description and the Atomic Tests to see exactly what the attacker does on a host or network.
  2. Find the telemetry - what data source would reveal it (process creation, registry, network flow, auth logs). Detection Coverage shows which surfaces already have a rule and which are blind.
  3. Get or write the detection - adapt ready logic (CAR Analytics, SIEM Detections, Falco, or Sigma via Generate a SIEM detection), or author your own.
  4. Test it - run an Atomic Test in a lab and confirm your rule actually fires. A detection you have not tested is a hope, not coverage.
  5. Deploy and tune - push it, then watch for false positives and adjust.
What each panel is for:
Atomic Testssafely reproduce the technique in a lab to validate that a detection fires. Detection Coveragewhich detection surfaces have a rule for this technique; none is a blind spot to close, or simply not applicable (YARA matches files, not network behaviour). CAR / SIEM / Falcoready-made detection logic (Splunk SPL, Elastic EQL, Sentinel KQL, Falco) you adapt to your own SIEM. Mitigationsreduce exposure so the technique is harder to use at all - prevent, not just detect. Actors / Attributionwho actually uses this, so you prioritise by your own threat model. Attack Path / LOTLwhat attackers do before and after this step, and the legitimate tools they abuse to do it.
Where this fits: you usually arrive here from a CVE (“which techniques does it enable”) and leave with a tested detection deployed. The buttons above jump straight to building one, the deployable rules, the CVEs that use T1172, and a hunt package.

Detection Coverage

0/9 layers
Coverage across standard detection surfaces. Rows marked none have no rule of that type mapped. Some are real blind spots worth closing; others are simply not applicable to this technique (e.g. YARA matches malware files, not network behaviour).
Behavioral / log (Sigma) none
Analytics (MITRE CAR) none
Runtime / container (Falco) none
File / malware (YARA) none
Network (Suricata/Snort) none
Vuln scan (Nuclei) none
SIEM (Splunk ESCU) none
SIEM (Elastic) none
SIEM (Azure Sentinel) none
External lookups - second-class, for what we don’t hold ourselves