战役归因证据分析 是做什么的?
概述
战役归因分析涉及系统评估证据,以确定哪个威胁行为者或团体对网络行动负责。本技能涵盖使用钻石模型和ACH(竞争假设分析法)收集和加权归因指标、分析基础设施重叠、TTP一致性、恶意软件代码相似性、操作时间模式以及语言痕迹,从而构建具有置信度权重的归因评估。
何时使用
- 当调查安全事件需要分析战役归因证据时
- 当为该领域构建检测规则或威胁狩猎查询时
- 当SOC分析师需要此分析类型的结构化流程时
- 当验证相关攻击技术安全监控覆盖率时
先决条件
- Python 3.9+,并安装
attackcti、stix2、networkx库 - 威胁情报平台(MISP、OpenCTI)的访问权限
- 理解入侵分析钻石模型
- 熟悉MITRE ATT&CK威胁团体资料
- 掌握恶意软件分析和基础设施追踪技术
关键概念
归因证据类别
- 基础设施重叠:共享的C2服务器、域名、IP范围、托管提供商
- TTP一致性:战役间匹配的ATT&CK技术和子技术
- 恶意软件代码相似性:共享代码库、编译器、PDB路径、加密例程
- 操作模式:时间(工作时间、时区)、目标选择模式、操作节奏
- 语言痕迹:特定语言的嵌入字符串、变量名、错误消息
- 受害目标特征:目标行业、地理位置和组织概况的一致性
置信度等级
- 高置信度:多个独立证据类别汇聚于同一行为者
- 中等置信度:若干证据类别匹配,但存在一些歧义
- 低置信度:证据有限,可能存在虚假标志或共享工具
竞争假设分析法(ACH)
一种结构化分析方法,对多个竞争性假设进行证据评估。每条证据相对于每个假设被评分为一致、不一致或中立。得分最低的不一致证据的假设被视为更优。
工作流程
步骤1:收集归因证据
from stix2 import MemoryStore, Filter
from collections import defaultdict
class AttributionAnalyzer:
def __init__(self):
self.evidence = []
self.hypotheses = {}
def add_evidence(self, category, description, value, confidence):
self.evidence.append({
"category": category,
"description": description,
"value": value,
"confidence": confidence,
"timestamp": None,
})
def add_hypothesis(self, actor_name, actor_id=""):
self.hypotheses[actor_name] = {
"actor_id": actor_id,
"consistent_evidence": [],
"inconsistent_evidence": [],
"neutral_evidence": [],
"score": 0,
}
def evaluate_evidence(self, evidence_idx, actor_name, assessment):
"""将证据与假设进行比对:一致/不一致/中立。"""
if assessment == "consistent":
self.hypotheses[actor_name]["consistent_evidence"].append(evidence_idx)
self.hypotheses[actor_name]["score"] += self.evidence[evidence_idx]["confidence"]
elif assessment == "inconsistent":
self.hypotheses[actor_name]["inconsistent_evidence"].append(evidence_idx)
self.hypotheses[actor_name]["score"] -= self.evidence[evidence_idx]["confidence"] * 2
else:
self.hypotheses[actor_name]["neutral_evidence"].append(evidence_idx)
def rank_hypotheses(self):
"""按归因分数对假设进行排序。"""
ranked = sorted(
self.hypotheses.items(),
key=lambda x: x[1]["score"],
reverse=True,
)
return [
{
"actor": name,
"score": data["score"],
"consistent": len(data["consistent_evidence"]),
"inconsistent": len(data["inconsistent_evidence"]),
"confidence": self._score_to_confidence(data["score"]),
}
for name, data in ranked
]
def _score_to_confidence(self, score):
if score >= 80:
return "HIGH"
elif score >= 40:
return "MODERATE"
else:
return "LOW"
步骤2:基础设施重叠分析
def analyze_infrastructure_overlap(campaign_a_infra, campaign_b_infra):
"""比较两个战役的基础设施以进行归因。"""
overlap = {
"shared_ips": set(campaign_a_infra.get("ips", [])).intersection(
campaign_b_infra.get("ips", [])
),
"shared_domains": set(campaign_a_infra.get("domains", [])).intersection(
campaign_b_infra.get("domains", [])
),
"shared_asns": set(campaign_a_infra.get("asns", [])).intersection(
campaign_b_infra.get("asns", [])
),
"shared_registrars": set(campaign_a_infra.get("registrars", [])).intersection(
campaign_b_infra.get("registrars", [])
),
}
overlap_score = 0
if overlap["shared_ips"]:
overlap_score += 30
if overlap["shared_domains"]:
overlap_score += 25
if overlap["shared_asns"]:
overlap_score += 15
if overlap["shared_registrars"]:
overlap_score += 10
return {
"overlap": {k: list(v) for k, v in overlap.items()},
"overlap_score": overlap_score,
"assessment": "STRONG" if overlap_score >= 40 else "MODERATE" if overlap_score >= 20 else "WEAK",
}
步骤3:跨战役TTP比较
from attackcti import attack_client
def compare_campaign_ttps(campaign_techniques, known_actor_techniques):
"""将战役TTP与已知威胁行为者资料进行比较。"""
campaign_set = set(campaign_techniques)
actor_set = set(known_actor_techniques)
common = campaign_set.intersection(actor_set)
unique_campaign = campaign_set - actor_set
unique_actor = actor_set - campaign_set
jaccard = len(common) / len(campaign_set.union(actor_set)) if campaign_set.union(actor_set) else 0
return {
"common_techniques": sorted(common),
"common_count": len(common),
"unique_to_campaign": sorted(unique_campaign),
"unique_to_actor": sorted(unique_actor),
"jaccard_similarity": round(jaccard, 3),
"overlap_percentage": round(len(common) / len(campaign_set) * 100, 1) if campaign_set else 0,
}
步骤4:生成归因报告
def generate_attribution_report(analyzer):
"""生成结构化的归因评估报告。"""
rankings = analyzer.rank_hypotheses()
report = {
"assessment_date": "2026-02-23",
"total_evidence_items": len(analyzer.evidence),
"hypotheses_evaluated": len(analyzer.hypotheses),
"rankings": rankings,
"primary_attribution": rankings[0] if rankings else None,
"evidence_summary": [
{
"index": i,
"category": e["category"],
"description": e["description"],
"confidence": e["confidence"],
}
for i, e in enumerate(analyzer.evidence)
],
}
return report
验证标准
- 证据收集覆盖全部六个归因类别
- ACH矩阵正确评估证据与竞争假设的关系
- 基础设施重叠分析识别共享指标
- TTP比较使用ATT&CK技术ID以确保精确性
- 归因置信度等级得到合理证明
- 报告包含备选假设和虚假标志考量