Challenge Library
Coding Challenges
5,893 curated questions across every arena — browse by topic, then jump into a live 3-minute battle to put them to the test.
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44 challenges matching your filters
Clear topic filter- Multiple ChoiceHard
[Security] Allow-Origin Cross-origin safeguarding
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Preflight Cross-origin safeguarding
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Credentials Cross-origin safeguarding
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Expose headers Cross-origin safeguarding
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Max-Age Cross-origin safeguarding
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Token Force user to perform unwanted actions
qasecuritysecurityqa - Multiple ChoiceHard
[Security] SameSite cookie Force user to perform unwanted actions
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Origin header Force user to perform unwanted actions
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Double submit Force user to perform unwanted actions
qasecuritysecurityqa - Multiple ChoiceHard
[Security] X-Requested-With Force user to perform unwanted actions
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] TLS handshake Transport security
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Certificate chains Transport security
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] HSTS Transport security
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Perfect forward secrecy Transport security
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] ALPN Transport security
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Structure Stateless authentication token
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Not encrypted Stateless authentication token
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Refresh token Stateless authentication token
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] jti Stateless authentication token
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] None algorithm Stateless authentication token
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Authorization code Delegated authorization
qasecuritysecurityqa - Multiple ChoiceHard
[Security] PKCE Delegated authorization
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Client credentials Delegated authorization
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Device flow Delegated authorization
qasecuritysecurityqa - Multiple ChoiceHard
[Security] Token rotation Delegated authorization
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] bcrypt Hashing and storage
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Argon2 Hashing and storage
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Salt Hashing and storage
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Pepper Hashing and storage
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Constant-time compare Hashing and storage
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Prepared stmt Malicious SQL in user input
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] ORM Malicious SQL in user input
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Second-order Malicious SQL in user input
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Blind SQLi Malicious SQL in user input
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Batched Malicious SQL in user input
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Stored Inject scripts into pages
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] Reflected Inject scripts into pages
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] DOM-based Inject scripts into pages
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] CSP Inject scripts into pages
qasecuritysecurityqa - Multiple ChoiceIntermediate
[Security] HttpOnly Inject scripts into pages
qasecuritysecurityqa - Multiple ChoiceHard
Service Mesh mTLS
mtlsservice-meshsecurity - Multiple ChoiceIntermediate
STRIDE Threat Modeling
stridethreat-modelingsecurity - Multiple ChoiceIntermediate
Refresh token rotation security
oauth2refresh-tokenrotationsecurity - Code AnalysisIntermediate
JWT introspection missing signature check
identityjwtoidcsecurity
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Every challenge here is drawn from the live Code Royale pool. Review a question, then head to the arena to answer under pressure against a real opponent — 3-minute matches, Elo ranking, and badge tiers on the line.