Vault-Associate Questions and Answers

The PKI secrets engine is designed to support the use case of reducing and ultimately removing the use of long lived X.509 certificates. The PKI secrets engine can generate dynamic X.509 certificates on demand, with short time-to-live (TTL) and automatic revocation. This eliminates the need for manual processes of generating, signing, and rotating certificates, and reduces the risk of certificate compromise or misuse. The PKI secrets engine can also act as a certificate authority (CA) or an intermediate CA, and can integrate with external CAs or CRLs. The PKI secrets engine can issue certificates for various purposes, such as TLS, SSH, code signing, email encryption, etc. References: https://developer.hashicorp.com/vault/docs/secrets/pki 1, https://developer.hashicorp.com/vault/tutorials/getting-started/getting-started-dynamic-secrets

The vault lease operations that use a lease_id as an argument are renew and revoke. The renew operation allows a client to extend the validity of a lease associated with a secret or a token. The revoke operation allows a client to terminate a lease immediately and invalidate the secret or the token. Both operations require a lease_id as an argument to identify the lease to be renewed or revoked. The lease_id can be obtained from the response of reading a secret or creating a token, or from the vault lease list command. The other operations, revoke-prefix, create, and describe, do not use a lease_id as an argument. The revoke-prefix operation allows a client to revoke all secrets or tokens generated under a given prefix. The create operation allows a client to create a new lease for a secret. The describe operation allows a client to view information about a lease, such as its TTL, policies, and metadata. References: Lease, Renew, and Revoke | Vault | HashiCorp Developer, vault lease - Command | Vault | HashiCorp Developer

To make an authenticated request via the Vault HTTP API, you need to use the X-Vault-Token HTTP Header or the Authorization HTTP Header using the Bearer scheme. The token is a string that represents your identity and permissions in Vault. You can obtain a token by using an authentication method, such as userpass, approle, aws, etc. The token can also be a root token, which has unlimited access to Vault, or a wrapped token, which is a response-wrapping token that can be used to unwrap the actual token. The token must be sent with every request to Vault that requires authentication, except for the unauthenticated endpoints, such as sys/init, sys/seal-status, sys/unseal, etc. The token is used by Vault to verify your identity and enforce the policies that grant or deny access to various paths and operations. References: https://developer.hashicorp.com/vault/api-docs 3, https://developer.hashicorp.com/vault/docs/concepts/tokens 4, https://developer.hashicorp.com/vault/docs/concepts/auth 5

The Transit secrets engine supports the rotation of encryption keys, which allows you to change the key that is used to encrypt new data without affecting the ability to decrypt data that was already encrypted. This reduces the amount of content encrypted with a single key in case the key gets compromised, and also helps you comply with the NIST guidelines for key rotation. You can rotate the encryption key manually by invoking the /transit/keys//rotate endpoint, or you can configure the key to automatically rotate based on a time interval or a number of encryption operations. When you rotate a key, Vault generates a new key version and increments the key’s latest_version metadata. The new key version becomes the encryption key used for encrypting any new data. The previous key versions are still available for decrypting the existing data, unless you specify a minimum decryption version to archive the old key versions. You can also delete or disable old key versions if you want to revoke access to the data encrypted with those versions. References: https://developer.hashicorp.com/vault/docs/secrets/transit 1, https://developer.hashicorp.com/vault/api-docs/secret/transit 2

Using a short-lived dynamic secrets can help limit the scope of a credential breach by reducing the exposure time of the secrets. Dynamic secrets are generated on-demand by Vault and automatically revoked when they are no longer needed. This way, the credentials are not stored in plain text or in a static database, and they can be rotated frequently to prevent unauthorized access. Dynamic secrets also provide encryption as a service, which means that they perform cryptographic operations on data in-transit without storing any data. This adds an extra layer of security and reduces the risk of data leakage or tampering. References: Dynamic secrets | Vault | HashiCorp Developer, What are dynamic secrets and why do I need them? - HashiCorp

When unsealing Vault, each Shamir unseal key should be entered by different administrators each connecting from different computers. This is because the Shamir unseal keys are split into shares that are distributed to trusted operators, and no single operator should have access to more than one share. This way, the unseal process requires the cooperation of a quorum of key holders, and enhances the security and availability of Vault. The unseal keys can be entered via multiple mechanisms from multiple client machines, and the process is stateful. The order of the keys does not matter, as long as the threshold number of keys is reached. The unseal keys should not be entered at the command line in one single command, as this would expose them to the history and compromise the security. The unseal keys should not be encrypted with each administrator’s PGP key, as this would prevent Vault from decrypting them and reconstructing the master key. References: https://developer.hashicorp.com/vault/docs/concepts/seal 3, https://developer.hashicorp.com/vault/docs/commands/operator/unseal

The root token is the initial token created when initializing Vault. It has unlimited privileges and can perform any operation in Vault. As a best practice, the root token should be revoked and never stored after initial setup. This is because the root token is a single point of failure and a potential security risk if it is compromised or leaked. Instead of using the root token, Vault operators should create other tokens with appropriate policies and roles that allow them to perform their tasks. If a new root token is needed in an emergency, the vault operator generate-root command can be used to create one on-the-fly with the consent of a quorum of unseal key holders. References: Tokens | Vault | HashiCorp Developer, Generate root tokens using unseal keys | Vault | HashiCorp Developer

The namespace can be defined in the “Mount path” field in the “Advanced options” section of the login screen. The mount path is the path where the auth method is enabled, and it can include a namespace prefix. For example, if the LDAP auth method is enabled at the pathns1/auth/ldap, where ns1 is the namespace, then the mount path field should be set to ns1/auth/ldap. This way, the Vault UI will log in to the correct namespace and auth method. Alternatively, the namespace can also be specified in the URL of the Vault UI, such as https://vault.example.com/ui/vault/auth/ns1/auth/ldap/login.

The transit secrets engine is not a good solution for binaries of this size, because it is designed to handle cryptographic functions on data in-transit, not data at-rest. The transit secrets engine does not store any data sent to it, so it would require sending the entire 2GB blob to Vault for encryption or decryption, which would be inefficient and impractical. A better solution would be to use the transit secrets engine to generate a data key, which is a high-entropy key that can be used to encrypt or decrypt data locally. The data key can be returned in plaintext or wrapped by another key, depending on the use case. This way, the transit secrets engine only handles the encryption or decryption of the data key, not the data itself, and the data can be stored in any primary data store. References: Transit - Secrets Engines | Vault | HashiCorp Developer, Encryption as a service: transit secrets engine | Vault | HashiCorp Developer

Dynamic secrets are generated on-demand by Vault and have a limited time-to-live (TTL). They do not ensure that administrators can see every password used, as they are often encrypted and ephemeral. The benefits of dynamic secrets are:

• They support systems that do not natively provide a method of expiring credentials, such as databases, cloud providers, SSH, etc. Vault can revoke the credentials when they are no longer needed or when the lease expires.
• They minimize the damage of credentials leaking, as they are short-lived and can be easily rotated or revoked. If a credential is compromised, the attacker has a limited window of opportunity to use it before it becomes invalid.
• They replace cumbersome password rotation tools and practices, as Vault can handle the generation and revocation of credentials automatically and securely. This reduces the operational overhead and complexity of managing secrets.

References: https://developer.hashicorp.com/vault/tutorials/getting-started/getting-started-dynamic-secrets 1, https://developer.hashicorp.com/vault/docs/concepts/lease 2

The Vault’s auth method component is the component that performs authentication and assigns identity and policies to a client. It verifies a client against an internal or external system, and generates a token with the appropriate policies attached. The token can then be used to access the secrets and resources that are authorized by the policies. Vault supports various auth methods, such as userpass, ldap, aws, kubernetes, etc., that can integrate with different identity providers and systems. The auth method component can also handle token renewal and revocation, as well as identity grouping and aliasing. References: Auth Methods | Vault | HashiCorp Developer, Authentication - Concepts | Vault | HashiCorp Developer

The payload.json file that has the correct contents is C. This file contains a JSON object with a single key, “plaintext”, and a value that is the base64-encoded string of the data to be encrypted. This is the format that the Vault API expects for the transit encrypt endpoint1. The other files are not correct because they either have the wrong key name, the wrong value format, or the wrong JSON syntax.

References:

• Encrypt Data - Transit Secrets Engine | Vault | HashiCorp Developer