Knowledge Based Authentication

Knowledge-based authentication (KBA) is an authentication method that verifies a user's identity by asking them to provide specific information only they should know. This approach is used in many online and offline systems to verify the identity of the person attempting to access an account or service.

KBA typically involves two types: static and dynamic. Static KBA relies on pre-determined questions and answers that the user sets up during the account creation process. For example, a user might be asked to provide their mother's maiden name, the name of their first pet, or the street they grew up on. These questions are designed to be personal and unique to the individual, making it difficult for unauthorized users to guess the correct answers.

Dynamic KBA is more sophisticated and involves generating questions based on the user's personal information, often obtained from credit reports or other data sources. These questions are typically more specific and less predictable, such as "What was the make and model of your first car?" or "What was the amount of your last credit card payment?" The advantage of dynamic KBA is that the questions are not pre-determined and can vary each time the user attempts to authenticate, making the authentication more secure.

Despite its widespread use, KBA has several limitations and security concerns. One of the main issues is that the answers to KBA questions can often be found through social engineering attacks or data breaches. For example, a user's mother's maiden name or the name of their first pet might be publicly available on social media or other online platforms. Additionally, if a user's personal information is compromised in a data breach, the answers to dynamic KBA questions can be easily obtained by attackers, rendering the authentication method ineffective. In light of these challenges, many organizations are exploring alternative authentication methods that offer better security and user convenience. Multifactor authentication (MFA), which can be used to combine KBA with other forms of verification such as biometrics or one-time codes sent to a user's mobile device, is becoming increasingly popular. MFA adds an extra layer of security by requiring multiple pieces of evidence to verify a user's identity, making it much harder for attackers to gain unauthorized access.