Threat modeling (STRIDE, DREAD) in Cybersecurity - Step-by-Step Execution

Concept Flow - Threat modeling (STRIDE, DREAD)

Identify Assets

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Identify Threats using STRIDE

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Assess Threats using DREAD

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Prioritize Threats

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Plan Mitigations

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Review and Update

The flow starts by identifying what to protect, then finds threats using STRIDE, assesses their risk with DREAD, prioritizes them, plans defenses, and repeats regularly.

Execution Sample

Cybersecurity

Assets = ['User Data', 'Server']
Threats = STRIDE(Assets)
Risks = DREAD(Threats)
Prioritize(Risks)
Mitigate(TopRisks)

This pseudocode shows identifying assets, finding threats with STRIDE, scoring risks with DREAD, prioritizing, and mitigating top risks.

Analysis Table

Step	Action	Details	Result
1	Identify Assets	List important things to protect	Assets = ['User Data', 'Server']
2	Apply STRIDE	Check each asset for Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege	Threats = ['Spoofing User Data', 'Tampering Server', ...]
3	Apply DREAD	Rate each threat on Damage, Reproducibility, Exploitability, Affected Users, Discoverability (scale 1-10)	Risks = {'Spoofing User Data': 35, 'Tampering Server': 40, ...}
4	Prioritize	Sort threats by DREAD score descending	TopRisks = ['Tampering Server', 'Spoofing User Data', ...]
5	Plan Mitigations	Decide how to reduce top risks	Mitigations planned for top threats
6	Review and Update	Repeat process regularly to catch new threats	Threat model updated

💡 Process ends after planning mitigations and scheduling reviews

State Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	Final
Assets	[]	['User Data', 'Server']	['User Data', 'Server']	['User Data', 'Server']	['User Data', 'Server']	['User Data', 'Server']
Threats	[]	[]	['Spoofing User Data', 'Tampering Server', 'Repudiation', 'Information Disclosure', 'Denial of Service', 'Elevation of Privilege']	['Spoofing User Data', 'Tampering Server', 'Repudiation', 'Information Disclosure', 'Denial of Service', 'Elevation of Privilege']	['Spoofing User Data', 'Tampering Server', 'Repudiation', 'Information Disclosure', 'Denial of Service', 'Elevation of Privilege']	['Spoofing User Data', 'Tampering Server', 'Repudiation', 'Information Disclosure', 'Denial of Service', 'Elevation of Privilege']
Risks	{}	{}	{}	{'Spoofing User Data': 35, 'Tampering Server': 40, 'Repudiation': 20, 'Information Disclosure': 30, 'Denial of Service': 25, 'Elevation of Privilege': 15}	{'Tampering Server': 40, 'Spoofing User Data': 35, 'Information Disclosure': 30, 'Denial of Service': 25, 'Repudiation': 20, 'Elevation of Privilege': 15}	{'Tampering Server': 40, 'Spoofing User Data': 35, 'Information Disclosure': 30, 'Denial of Service': 25, 'Repudiation': 20, 'Elevation of Privilege': 15}
TopRisks	[]	[]	[]	[]	['Tampering Server', 'Spoofing User Data', 'Information Disclosure', 'Denial of Service', 'Repudiation', 'Elevation of Privilege']	['Tampering Server', 'Spoofing User Data', 'Information Disclosure', 'Denial of Service', 'Repudiation', 'Elevation of Privilege']

Key Insights - 3 Insights

Why do we use STRIDE before DREAD?

STRIDE helps find different types of threats first (see execution_table step 2), then DREAD scores their risk (step 3). Without STRIDE, we might miss threats to score.

What does a high DREAD score mean?

A high DREAD score (execution_table step 3) means the threat is more dangerous or likely, so it should be prioritized for mitigation (step 4).

Why do we review and update the threat model regularly?

New threats appear over time. Regular review (step 6) keeps the model current and defenses effective.

Visual Quiz - 3 Questions

Look at the execution_table at step 3. What does the DREAD score represent?

A The risk level of each threat

B The number of assets

C The list of mitigations

D The types of threats

💡 Hint

Check the 'Details' and 'Result' columns at step 3 in execution_table

At which step in the execution_table do we decide which threats to fix first?

A Step 1

B Step 2

C Step 4

D Step 6

💡 Hint

Look for the step where threats are sorted by risk

If a new asset is added after step 1, how would the variable 'Threats' change?

A It would stay the same

B It would include threats related to the new asset

C It would remove old threats

D It would only list mitigations

💡 Hint

Refer to variable_tracker for how Threats depend on Assets

Concept Snapshot

Threat modeling helps find and fix security risks.
STRIDE finds threat types: Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege.
DREAD scores threats by Damage, Reproducibility, Exploitability, Affected users, Discoverability.
Use STRIDE first to identify threats, then DREAD to prioritize.
Plan mitigations for top risks and review regularly.

Full Transcript

Threat modeling is a process to find and fix security risks. First, identify what you want to protect, called assets. Then use STRIDE to find different types of threats to those assets. STRIDE stands for Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, and Elevation of Privilege. After listing threats, use DREAD to score each threat's risk. DREAD scores Damage potential, Reproducibility, Exploitability, Affected users, and Discoverability on a scale. Higher scores mean higher risk. Sort threats by their DREAD scores to decide which to fix first. Plan how to reduce these risks with mitigations. Finally, review and update the threat model regularly to catch new risks. This step-by-step process helps keep systems safer by focusing on the most serious threats first.