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How detection works

The four layers every event passes through, what each one catches that the others miss, and the multi-step patterns joined on top of them.

Every event goes through the same four layers, whether it came from the Windows agent, an SSH server, a log file or the API. An event that one layer misses can still be caught by another.

Detection rules match an event’s fields, tags and type. A rule fires only when every condition it states holds. Each rule carries its MITRE ATT&CK techniques, a severity and notes on known false positives; most also carry test events that prove they fire, and stay quiet when they should. See Detection rules.

Some rules depend on tags computed from earlier events when a new one arrives. Among them:

Tag Set when
Brute force 5 or more failed logins from one address, or for one account, within 10 minutes
Port scan One source reaches 15 or more ports within 2 minutes — or 40 or more within 24 hours, for a slow scan
Host discovery ICMP probes from one source to 10 or more hosts within 2 minutes
Beaconing Connections from one source to one destination at regular intervals: at least 6 in 30 minutes with a spread of at most 15%. A looser test catches beacons with deliberate jitter.
SMB lateral movement One source reaches 3 or more hosts on port 445 within 5 minutes
Kerberoasting Kerberos service-ticket requests for 5 or more different services from one source within 2 minutes
DNS tunnelling 30 or more different subdomain queries from one source within 5 minutes
Mass file change 50 or more files created or changed on one host within 2 minutes
Off-hours admin An administrator logs on, or gains privileges, outside the tenant’s working hours or at the weekend. Working hours and time zone are set per tenant.

Attacks that never write a file show up in command lines and process relationships. The heuristics read every process event for:

Behaviour ATT&CK
Encoded or download-and-run PowerShell T1059.001
Living-off-the-land binaries used to run code T1218
Reading LSASS memory T1003.001
Process injection, DLL injection, process hollowing T1055, T1055.001, T1055.012
WMI used to execute T1047
Scheduled tasks created from the command line T1053.005
DLL search-order hijacking T1574.001
Active Directory and domain-trust enumeration, Kerberoasting T1087.002, T1482, T1558.003
Network, remote-system, security-software and cloud discovery T1046, T1018, T1518.001, T1526

The platform learns each user, host, address, process and domain: how many events it produces a day, at which hours, and which kinds. Nothing is judged until the entity has seven days of history, so the baseline has seen working days and a weekend.

After that, a day whose volume is three standard deviations or more above the entity’s norm raises an alert — high, or critical at five. Activity at an hour that held under 1% of the entity’s history, and an event type never seen from it, are scored but do not raise alerts on their own.

Single events are tied to stages — credential attack, login, execution, persistence, credential dumping, evasion, lateral movement, impact. Only events that a rule or heuristic already flagged count as a stage; a successful login counts as context. When one host shows these combinations within 30 minutes, the platform raises one alert that names the chain:

Chain Stages Severity
Credential compromise in progress Credential attack + login High
Active intrusion — credential dumping Login + credential dumping Critical
Foothold established Persistence + execution High
Defense evasion + execution Evasion + execution High
Pre-lateral movement Credential dumping + lateral movement Critical
Full attack chain Credential attack + execution + persistence + lateral movement Critical
Impact phase Persistence + impact Critical

Four correlation rules join events across sources:

Rule Pattern Window
Brute force → successful login 5 or more failed logins, then a success, from the same address 10 minutes
Recon → exploitation A port scan on a target, then an exploitation attempt on it 60 minutes
Lateral movement chain A successful login on one server, then on another, from the same source 30 minutes
Data staging → exfiltration 100 or more file accesses, then a large outbound transfer, from one asset 2 hours

Impossible travel — the same user logging in from places too far apart for the time between — is checked as well.