triage-suspicious-login

Suspicious Login Triage Skill

Guide initial triage of suspicious login alerts (impossible travel, untrusted location, multiple failed logins) for Tier 1 SOC Analysts.

Inputs

• CASE_ID - SOAR case ID containing the alert(s)
• ALERT_GROUP_IDENTIFIERS - Alert group identifiers from the case
• (Optional) USER_ID - The user ID if known upfront
• (Optional) SOURCE_IP - The source IP if known upfront

Workflow

Step 1: Get Case Context

secops-soar.get_case_full_details(case_id=CASE_ID)

Step 2: Extract Key Entities

secops-soar.list_events_by_alert(case_id=CASE_ID, alert_id=ALERT_ID)

Parse events to extract:

• USER_ID - The user account
• SOURCE_IP - The login source IP
• HOSTNAME - The target/source hostname (if available)

Step 3: User Context (SIEM)

secops-mcp.lookup_entity(entity_value=USER_ID)

Record: Recent activity, first/last seen, related alerts.

Step 4: Source IP Enrichment

Use /enrich-ioc with IOC_TYPE="IP Address":

• GTI reputation and geolocation
• SIEM entity summary
• IOC match status

Step 5: Hostname Context (if available)

secops-mcp.lookup_entity(entity_value=HOSTNAME)

Step 6: Recent Login Activity

Search for login patterns over the last 96 hours:

secops-mcp.search_security_events(
    text='metadata.event_type IN ("USER_LOGIN", "AUTH_ATTEMPT") AND principal.user.userid = "USER_ID"',
    hours_back=96
)

Analyze for:

• Logins from unusual IPs
• Successful logins after failures
• Geographic anomalies (impossible travel)
• Concurrent sessions from different locations

Step 7: Check Related Cases

Use /find-relevant-case with search terms: [USER_ID, SOURCE_IP, HOSTNAME]

Step 8: (Optional) Identity Provider Check

If IDP tools available (e.g., Okta):

• Account status
• MFA enrollment
• Recent legitimate logins
• Password change history

Step 9: Synthesize & Document

Use /document-in-case with findings summary:

Suspicious Login Triage for USER_ID from SOURCE_IP:
- User SIEM Summary: [...]
- Source IP GTI: [reputation, geo]
- Login Pattern: [normal/anomalous]
- Related Cases: [...]
- Recommendation: [Close as FP | Escalate to Tier 2]

Required Outputs

After completing this skill, you MUST report these outputs:

| Output | Description | |--------|-------------| | LOGIN_VERDICT | Assessment: legitimate, suspicious, or malicious | | ANOMALY_INDICATORS | What made the login suspicious (impossible travel, new device, etc.) | | RELATED_ACTIVITY | Other suspicious activity from user or source IP | | RISK_SCORE | Numerical risk assessment (0-100) based on findings |

Decision Matrix

| Finding | Recommendation | |---------|----------------| | Known VPN/corporate IP + normal pattern | Close as FP | | User confirmed travel + MFA used | Close as Benign TP | | Malicious IP reputation | Escalate | | Impossible travel + no MFA | Escalate urgently | | Multiple failures then success from new IP | Escalate | | Pattern matches user's normal behavior | Close as FP |

Key Patterns to Detect

Impossible Travel:

• Login from NYC, then London 30 mins later
• Check if VPN or cloud service could explain

Credential Stuffing:

• Many failures across multiple accounts from same IP
• Success after many failures

Account Takeover:

• Login from new device/location
• Followed by password change or MFA modification

Lateral Movement:

• Same user logging into many systems rapidly
• Unusual service account activity