Which STRIDE threat component involves the act of disputing an identity or action?

Repudiation refers to the act of denying the validity of an identity or an action. This threat component is concerned with situations where an individual or entity denies having performed an action, such as sending a message or completing a transaction. In the context of cybersecurity, repudiation can lead to significant issues because it makes it difficult to establish accountability.

For example, if a user conducts a financial transaction and later claims they did not authorize it, that denial can create challenges for detection and response to fraud. Tools and mechanisms that provide non-repudiation, such as digital signatures and logging, are important for mitigating this threat, as they ensure that users cannot easily deny their actions or identity.

The other components mentioned represent different types of security threats. Denial of Service involves overwhelming a system to disrupt service, spoofing identity refers to impersonating another user to gain unauthorized access, and tampering with data involves unauthorized modification of data. Each of these threats has unique characteristics and implications, but none specifically focus on the aspect of denying an action or identity, making repudiation the correct and relevant choice.