An incident built from a Rapid7 investigation indexed zero entities. Nothing to
pivot on, nothing to correlate, and an AI analysis with nothing to read. The
reason turned out not to be the mapper but the feed: an investigation is an
envelope, and neither it nor its /alerts list carries a host, an account, a
process or a MITRE code.
The Alert Triage API does, in rule_keys_of_interest. On the alert behind the
investigation that started this, that field holds:
hostname NBSGIT01-26
process.name bcdedit.exe
process.cmd_line bcdedit /set {default} recoveryenabled No
process.exe_path C:\WINDOWS\System32\bcdedit.exe
parent_process.name cmd.exe
parent_process.cmd_line "C:\WINDOWS\system32\cmd.exe"
parent_process.exe_file.hashes.md5 e463e36104d22a2479046a7d4f620816
with rule.mitre_tcodes ["TA0040", "T1490"] — Impact / Inhibit System Recovery,
which is what disabling Windows recovery actually is. None of it was reachable
before.
It is a list of {key, values} pairs rather than an object, so every entry reads
through a JSONata predicate — rule_keys_of_interest[key='hostname'].values[0].
A key a rule does not emit resolves to nothing and is skipped, so one file
covers every detection rule.
Two details worth keeping:
- mitre_tcodes mixes tactics and techniques in one array ("TA0040" beside
"T1490"). They are split on the "TA" prefix so a tactic never lands in the
technique field, where it would name a technique that does not exist.
- rule.name is documented but absent from live ABA alerts, so the analytic
name falls back to `type`, which repeats the rule's display name.
Rapid7's own status, disposition and AI-suggested disposition ride as custom
fields. They cannot reach the incident's status and verdict columns — MapFields
accepts only title, severity, source, description and custom:* — but an analyst
can at least see that the source already closed the alert and what it decided.
The AI suggestion is exposed as a fact, never as a verdict.
Validated end to end against a live alert: field mapping, OCSF mapping and
entity extraction, which now yields the host and the parent process hash where
it previously yielded nothing.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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