Censorship Attack
Pronunciation: SEHN-sur-shihp uh-TAK
Definition
Censorship Attack is an attack or weakness pattern that deliberately prevents selected valid transactions or users from receiving normal processing, confirmation, relay, or network access. For Censorship Attack, an attempted action, a detected indicator, a confirmed compromise, and a realized loss are separate states that require different evidence and response.
Overview
Meaning and scope
Censorship Attack is an attack or weakness pattern that deliberately prevents selected valid transactions or users from receiving normal processing, confirmation, relay, or network access. For Censorship Attack, an attempted action, a detected indicator, a confirmed compromise, and a realized loss are separate states that require different evidence and response.
Mechanism and operation
Attackers may control block production, relays, validators, gateways, infrastructure, or network connectivity and then exclude transactions matching chosen addresses, fees, contracts, or policies. Even without majority control, concentrated infrastructure or coordinated operators may delay activity long enough to cause liquidation, missed payments, governance failure, or loss of commercial opportunity. Defenses include diverse validators and relays, alternate submission channels, inclusion monitoring, encrypted or private transaction paths, economic penalties, and fallback execution. Response plans should distinguish ordinary congestion from selective exclusion using comparative evidence across users, routes, and time. A theoretical weakness or scanner result involving selected valid transactions, users from receiving normal processing, and confirmation should not be reported as exploitation without corroborating logs, transactions, or configuration evidence.
Practical payment example
An adversarial validator group systematically excludes a class of transactions, and operators distinguish the behavior from ordinary congestion.
Operational checks
Assessment of Censorship Attack should trace prevention of selected valid transactions or users from receiving normal processing, confirmation, relay, or network access from prerequisite and entry point through observable impact on the affected service. Prevention, detection, containment, and recovery for the Censorship attack path should be tested against the architecture associated with selected valid transactions, users from receiving normal processing, and confirmation.
Distinctions and limits
A censorship attack targets availability and fair inclusion rather than directly forging ownership. A censorship attack harms reliable inclusion, and detection requires showing selective exclusion rather than merely slow processing or general congestion.
Related reading
Related definitions: block production, transaction.
Example
An adversarial validator group systematically excludes a class of transactions, and operators distinguish the behavior from ordinary congestion.
Comparison
A censorship attack targets availability and fair inclusion rather than directly forging ownership. A censorship attack harms reliable inclusion, and detection requires showing selective exclusion rather than merely slow processing or general congestion.
Key Takeaway
A censorship attack harms reliable inclusion, and detection requires showing selective exclusion rather than merely slow processing or general congestion.
Sources
- NIST Documentation: Cyberframework — NIST (2026-07-30)
- FATF Documentation: Virtual Assets — FATF (2026-07-30)