Objective 4.3High13 min

Vulnerability Identification Methods

Techniques for finding vulnerabilities including vulnerability scanning, SAST, DAST, threat intelligence feeds, OSINT, and penetration testing methodologies.

Understanding Vulnerability Identification Methods

Vulnerability identification discovers security weaknesses before attackers do. Multiple methods exist because no single technique finds all vulnerabilities—defense requires layered approaches.

Key identification methods:Vulnerability scanning — Automated detection • Application testing — SAST, DAST, IAST • Threat intelligence — External vulnerability information • OSINT — Open source reconnaissance • Penetration testing — Simulated attacks

The 2017 Equifax breach exploited a known Apache Struts vulnerability that had a patch available for two months. Equifax's vulnerability scanning program failed to identify the vulnerable server, demonstrating that identification must be comprehensive and continuous.

Finding vulnerabilities first is essential—attackers are always looking.

Why This Matters for the Exam

Vulnerability identification is heavily tested on SY0-701 because it's fundamental to security operations. Questions cover scan types, application testing, and threat intelligence sources.

Understanding identification methods helps with vulnerability management, risk assessment, and security testing. You can't fix what you don't find.

The exam tests recognition of identification methods and appropriate selection.

Deep Dive

What Is Vulnerability Scanning?

Vulnerability scanning uses automated tools to detect known vulnerabilities.

Scan Types:

TypeDescriptionUse Case
Network scanScan network devices/hostsInfrastructure
Web application scanScan web appsApplications
Database scanScan database configsData tier
Cloud scanScan cloud configurationsCloud security

Authenticated vs Unauthenticated:

Unauthenticated (external view):
- No credentials
- Sees what attacker sees
- Fewer findings
- May miss internal vulnerabilities
- Faster, less intrusive

Authenticated (internal view):
- Uses credentials
- Deeper inspection
- More findings
- Sees patch levels
- More accurate results

Scan Comparison:

AspectUnauthenticatedAuthenticated
CredentialsNoneValid account
DepthSurfaceDeep
AccuracyMore false positivesMore accurate
CoverageExternal viewInternal view
Use casePerimeter testingComplete assessment

What Is Application Security Testing?

Application testing finds vulnerabilities in software.

SAST (Static Application Security Testing):

What: Analyzes source code without executing
When: During development (shift left)
Finds: Coding errors, SQL injection paths, XSS sources

Pros:
- Finds issues early
- Complete code coverage
- No running application needed

Cons:
- Many false positives
- Can't find runtime issues
- Requires source code access

DAST (Dynamic Application Security Testing):

What: Tests running application
When: Testing/staging environment
Finds: Runtime vulnerabilities, authentication issues

Pros:
- Tests real behavior
- Finds runtime issues
- No source code needed

Cons:
- Requires running application
- Can't find dormant code issues
- May not achieve full coverage

IAST (Interactive Application Security Testing):

What: Combines SAST and DAST, instruments application
When: During testing with real traffic
Finds: Both code and runtime issues

Pros:
- More accurate (fewer false positives)
- Real-time feedback
- Correlates code to runtime

Cons:
- Requires instrumentation
- May affect performance
- Complex setup

Testing Comparison:

AspectSASTDASTIAST
TestsSource codeRunning appBoth
WhenDevelopmentTestingTesting
False positivesHighMediumLow
CoverageCode pathsExposed functionalityBoth

What Are Threat Intelligence Feeds?

Threat feeds provide external vulnerability and threat information.

Feed Types:

TypeContent
Vulnerability feedsNew CVEs, exploits
Indicator feedsIOCs, malware hashes
Reputation feedsBad IPs, domains
Strategic feedsThreat actor TTPs

Intelligence Sources:

Commercial:
- Recorded Future
- Mandiant
- CrowdStrike

Open source:
- CISA alerts
- US-CERT
- MITRE ATT&CK
- AlienVault OTX

Industry:
- ISACs (sector-specific)
- FS-ISAC (financial)
- H-ISAC (healthcare)

What Is OSINT?

Open Source Intelligence gathers publicly available information about your organization's exposure.

OSINT Sources:

SourceInformation
Search enginesExposed documents, configs
Social mediaEmployee info, company details
Code reposLeaked credentials, code
Paste sitesData leaks
DNS/WHOISInfrastructure details
Shodan/CensysExposed devices

OSINT for Vulnerability Assessment:

Find:
- Exposed services (Shodan)
- Leaked credentials (paste sites)
- Developer mistakes (GitHub)
- Domain information (DNS)
- Certificate transparency logs

Purpose:
- See what attackers see
- Find shadow IT
- Identify exposure
- Assess attack surface

What Is Penetration Testing?

Penetration testing simulates real attacks to find exploitable vulnerabilities.

Penetration Test Types:

TypeKnowledgeSimulates
Black boxNo info givenExternal attacker
White boxFull info givenInsider/audit
Gray boxPartial infoTargeted attacker

Penetration Test Phases:

1. Planning/Scoping
   - Define targets
   - Set rules of engagement
   - Get authorization

2. Reconnaissance
   - OSINT gathering
   - Network mapping
   - Service enumeration

3. Vulnerability Assessment
   - Identify weaknesses
   - Plan attacks

4. Exploitation
   - Attempt to exploit
   - Gain access

5. Post-Exploitation
   - Privilege escalation
   - Lateral movement
   - Data access

6. Reporting
   - Document findings
   - Provide remediation

Rules of Engagement:

Define:
- Scope (what to test)
- Methods (what's allowed)
- Timing (when to test)
- Contacts (who to notify)
- Boundaries (what's off-limits)
- Authorization (written approval)

How CompTIA Tests This

Example Analysis

Scenario: A company wants to implement a comprehensive vulnerability identification program. They have web applications, internal networks, cloud infrastructure, and mobile apps. Design an identification strategy.

Analysis - Comprehensive Vulnerability Identification:

Asset Categories:

1. Web applications (10 customer-facing)
2. Internal network (500 hosts)
3. Cloud infrastructure (AWS)
4. Mobile applications (iOS/Android)

Identification Methods by Asset:

Web Applications:

Development phase:
- SAST: Analyze source code during CI/CD
- Tool: SonarQube, Checkmarx
- Frequency: Every commit

Testing phase:
- DAST: Test running applications
- Tool: OWASP ZAP, Burp Suite
- Frequency: Before each release

Production:
- Web application scanning
- Tool: Qualys WAS, Nessus
- Frequency: Weekly

Annual:
- Penetration testing (third-party)
- Scope: All customer-facing apps

Internal Network:

Authenticated scanning:
- Tool: Nessus, Qualys
- Credentials: Domain admin equivalent
- Frequency: Weekly
- Coverage: All 500 hosts

Unauthenticated scanning:
- Tool: Same
- Frequency: Monthly
- Purpose: External attacker view

Discovery scanning:
- Find new/unknown devices
- Compare to asset inventory
- Frequency: Daily

Cloud Infrastructure:

Configuration scanning:
- Tool: AWS Config, Prowler, ScoutSuite
- Check: CIS benchmarks, security groups
- Frequency: Continuous

Infrastructure scanning:
- Tool: Cloud-native scanner
- Targets: EC2 instances, containers
- Frequency: Weekly

Mobile Applications:

Static analysis:
- Tool: MobSF, Checkmarx
- Analyze: APK/IPA files
- When: Before release

Dynamic analysis:
- Tool: Frida, Objection
- Test: Runtime behavior
- When: Each release

Threat Intelligence Integration:

Feeds:
- CISA alerts (free)
- Commercial feed (Recorded Future)
- Industry ISAC (if applicable)

Integration:
- Feed into vulnerability scanner
- Prioritize known exploited vulns
- Alert on new critical CVEs

OSINT Monitoring:

Monitor for:
- Company name on paste sites
- Credentials in breaches
- Exposed services (Shodan)
- Code/config leaks (GitHub)

Tool: SpiderFoot, theHarvester
Frequency: Weekly

Key insight: Comprehensive identification requires multiple methods—SAST for code, DAST for running apps, authenticated scanning for infrastructure, cloud-specific tools for cloud, and threat intelligence for prioritization. No single tool finds everything.

Key Terms

vulnerability identificationvulnerability scanningSASTDASTthreat feedsOSINTpenetration testingauthenticated scan

Common Mistakes

Unauthenticated scans only—authenticated scans find significantly more vulnerabilities. Use both.
SAST or DAST alone—use both. SAST finds code issues, DAST finds runtime issues.
Ignoring threat intelligence—feeds help prioritize. Known exploited vulnerabilities need immediate attention.
No rules of engagement for pen tests—unauthorized testing is illegal. Always get written approval.

Exam Tips

Authenticated scan = uses credentials, deeper view, more accurate. Unauthenticated = external view.
SAST = Static (source code, no execution). DAST = Dynamic (running app). IAST = Both combined.
SAST is "shift left"—finds issues early in development.
Black box = no knowledge (external). White box = full knowledge (audit). Gray box = partial.
OSINT sources: Shodan (devices), paste sites (leaks), GitHub (code), social media.
Threat feeds: vulnerability info (CVEs), indicators (IOCs), reputation (bad IPs).

Memory Trick

Scan Types: "Authenticated = All-access pass (deep view)" "Unauthenticated = Unknown visitor (surface only)"

  • Application Testing - "SDI":
  • SAST = Source code (Static)
  • DAST = Deployed app (Dynamic)
  • IAST = Instrumented (Interactive)

Pen Test Types: "Black box = Blind (no info)" "White box = Wide open (full info)" "Gray box = Got some (partial info)"

  • OSINT Sources - "SSDPC":
  • Shodan (exposed devices)
  • Social media (people)
  • DNS/WHOIS (infrastructure)
  • Paste sites (leaks)
  • Code repos (secrets)

Pen Test Rule: "No Rules of Engagement = No testing" (REN) - Always get written authorization!

Test Your Knowledge

Q1.Which scan type provides the MOST accurate view of a system's vulnerabilities?

Q2.Which testing method analyzes source code WITHOUT executing the application?

Q3.A penetration tester is given no information about the target network. What type of test is this?

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