ATT&CK coverage › Technique

Data Encoding: Standard Encoding T1132.001

Adversaries may encode data with a standard data encoding system to make the content of command and control traffic more difficult to detect. Command and control (C2) information can be encoded using a standard data encoding system that adheres to existing protocol specifications. Common data encoding schemes include ASCII, Unicode, hexadecimal, Base64, and MIME. Some data encoding systems may also result in data compression, such as gzip.

Events covered

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

ProviderEvent IDTitle
Sysmon1Process creation
Security-Auditing4688A new process has been created.
PowerShell4104Creating Scriptblock text (MessageNumber of MessageTotal).

Authoring guide

Patterns shared across the 4 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 (3 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
CommandLine2match 2::Decompress, GZipStream, FromBase64String, H4sI, MemoryStream
Image1match 1, ends_with 1\dnscat2, \iodine.exe
ScriptBlockText1match 1FromBase64String, H4sI, MemoryStream

Top indicator values (10 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
Imagematch\dnscat21
Imageends_with\iodine.exe1
CommandLinematch::Decompress1
CommandLinematchGZipStream1
CommandLinematchFromBase64String17
CommandLinematchMemoryStream1
CommandLinematchH4sI1
ScriptBlockTextmatchFromBase64String1
ScriptBlockTextmatchMemoryStream1
ScriptBlockTextmatchH4sI1

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 4 rules