triaging-security-incident

name	triaging-security-incident
description	Performs initial triage of security incidents to determine severity, scope, and required response actions using the NIST SP 800-61r3 and SANS PICERL frameworks. Classifies incidents by type, assigns priority based on business impact, and routes to appropriate response teams. Activates for requests involving incident triage, security alert classification, severity assessment, incident prioritization, or initial incident analysis. . Use when working with triaging security incident.
domain	cybersecurity
tags	["incident-triage","NIST-800-61","SANS-PICERL","severity-classification","SOC-operations"]
subdomain	incident-response
mitre_attack	["T1190","T1566","T1078","T1059"]
version	1.0.0
author	oyi77
license	Apache-2.0
d3fend_techniques	["Executable Denylisting","Execution Isolation","File Metadata Consistency Validation","Content Format Conversion","File Content Analysis"]
nist_csf	["RS.MA-01","RS.MA-02","RS.AN-03","RC.RP-01"]

Triaging Security Incident

Overview

Cybersecurity skill for triaging security incident. Follows industry best practices and security standards.

When to Use

Trigger phrases:

• "triaging security incident"

• "Performs initial triage of security incidents to determine severity, scope, and "

• A SIEM or EDR alert fires and requires human classification before escalation

• Multiple concurrent alerts arrive and the SOC must prioritize response order

• An end user reports suspicious activity and the incident needs initial categorization

• A threat intelligence feed matches an IOC observed in the environment

Do not use for routine vulnerability scanning results or compliance audit findings that do not represent active security incidents.

When NOT to Use

• When you lack proper authorization for testing
• For production systems without change management
• When the task requires legal or compliance expertise beyond technical scope

Prerequisites

• Access to SIEM platform (Splunk, Elastic, Microsoft Sentinel) with current alert data
• Incident classification taxonomy aligned to NIST SP 800-61r3 categories
• Predefined severity matrix mapping asset criticality to threat type
• Contact roster for escalation paths (Tier 1 through Tier 3 and CIRT)
• Asset inventory with business criticality ratings

Workflow

# Example: IOC detection
import re

IOC_PATTERNS = {
    "ip": r"\b(?:\d{1,3}\.){3}\d{1,3}\b",
    "domain": r"\b[a-z0-9-]+\.[a-z]{2,}\b",
    "hash_md5": r"\b[a-f0-9]{32}\b",
    "hash_sha256": r"\b[a-f0-9]{64}\b",
}

def extract_iocs(text: str) -> dict:
    return {k: re.findall(v, text) for k, v in IOC_PATTERNS.items()}