Techniques › T1027.014 › AN0920
AN0920 Analytic 0920
Linux · attack.mitre.org · ATT&CK Enterprise v19.2
<p>Detects files or processes where execution results in frequent re-creation or modification of ELF binaries or interpreter scripts, often using chmod + execve with abnormal entropy.</p>
- Detects
- T1027.014 Polymorphic Code
- Part of
- DET0324 Detection Strategy for Polymorphic Code Mutation and Execution
Log sources and channels
Exactly as MITRE states them in x_mitre_log_source_references. Where a channel is vague, it is vague in the source; kevmap does not tidy it.
| Log source | Channel | Data component |
|---|---|---|
| auditd:SYSCALL | execve | DC0032 Process Creation |
| auditd:SYSCALL | mmap | DC0016 Module Load |
| auditd:SYSCALL | chmod | DC0061 File Modification |
Mutable elements
Parameters MITRE marks as environment-specific. These are the knobs you are expected to tune; they are why an analytic is not a rule.
| Field | Description |
|---|---|
WriteExecThreshold | Tune to alert on write followed by chmod + exec in quick succession. |
FileEntropyDeviation | Detect high deviation from average entropy score of baseline ELF/script files. |
ExecutionFrequency | Abnormal burst executions of file with identical functionality but varying hash. |