academy.security.krd

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Forty alerts a day

Medium · 20 points

A week of alert counts from four detection rules, with what each one turned out to be after review.

One of these rules is actively harmful: it is training whoever is on duty to close the queue without reading it. It is not simply the one that fires most — a rule can be busy and still earn its place, and a rule can be quiet and still be useless.

The number that decides it is not in the table. Sort by the column that is worked out for you, and ask of each rule: of everything it fired on, how much was worth a human's attention?

Identify the rule that should be tuned by exclusion, and submit its id as the flag: skrd{RULE-000}.

Artefact

rule      fired  confirmed  benign cause
--------  -----  ---------  ---------------------------------------------
RULE-014     11         9   remote service creation by non-admin accounts
RULE-027    283         0   backup agent reading every share nightly
RULE-031     46        12   password sprays against the mail gateway
RULE-052      3         3   new local admin created outside change window
Hint

Two hundred and eighty-three fires, nothing confirmed, one known cause. Exclude that account on that host for that action — do not delete the rule.