ATT&CK coverage › Technique

Encrypted Channel T1573

Adversaries may employ an encryption algorithm to conceal command and control traffic rather than relying on any inherent protections provided by a communication protocol. Despite the use of a secure algorithm, these implementations may be vulnerable to reverse engineering if secret keys are encoded and/or generated within malware samples/configuration files.

Events covered

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

ProviderEvent IDTitle
Sysmon22DNSEvent (DNS query)
PowerShell4104Creating Scriptblock text (MessageNumber of MessageTotal).

Authoring guide

Patterns shared across the 2 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 (2 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
EventResultDetails1match 1errors
ScriptBlockText1match 1Net.Security.RemoteCertificateValidationCallback, .AuthenticateAsClient, System.Net.Security.SslStream

Top indicator values (4 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
EventResultDetailsmatcherrors1
ScriptBlockTextmatch.AuthenticateAsClient1
ScriptBlockTextmatchSystem.Net.Security.SslStream1
ScriptBlockTextmatchNet.Security.RemoteCertificateValidationCallback1

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 1 rule

Kusto Query Language 1 rule