Most Recent HashiCorp Vault-Associate Exam Questions & Answers

The Vault secret engine that can be used to build your own internal certificate authority is the PKI secret engine. The PKI secret engine generates dynamic X.509 certificates on-demand, without requiring manual processes of generating private keys and CSRs, submitting to a CA, and waiting for verification and signing. The PKI secret engine can act as a root CA or an intermediate CA, and can issue certificates for various purposes, such as TLS, code signing, email encryption, etc. The PKI secret engine can also manage the certificate lifecycle, such as rotation, revocation, renewal, and CRL generation. The PKI secret engine can also integrate with external CAs, such as Venafi or Entrust, to delegate the certificate issuance and management.Reference:PKI - Secrets Engines | Vault | HashiCorp Developer,Build Your Own Certificate Authority (CA) | Vault - HashiCorp Learn

The error was thrown because the policy code contains an invalid capability, ''write''. The valid capabilities for a policy are ''create'', ''read'', ''update'', ''delete'', ''list'', and ''sudo''. The ''write'' capability is not recognized by Vault and should be replaced with ''create'', which allows creating new secrets or overwriting existing ones. The other statements are not correct, because the wildcard (*) and the sudo capability are both valid in a policy. The wildcard matches any number of characters within a path segment, and the sudo capability allows performing certain operations that require root privileges.

[Policy Syntax | Vault | HashiCorp Developer]

[Policy Syntax | Vault | HashiCorp Developer]

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.Reference: https://developer.hashicorp.com/vault/docs/concepts/seal3, https://developer.hashicorp.com/vault/docs/commands/operator/unseal

A web application that uses Vault's transit secrets engine to encrypt data in-transit can benefit from the following security features:

Even if the attacker was able to access the raw data, they would only have encrypted bits (TLS in transit). This means that the attacker would need to obtain the encryption key from Vault in order to decrypt the data, which is protected by Vault's authentication and authorization mechanisms. The transit secrets engine does not store the data sent to it, so the attacker cannot access the data from Vault either.

The keys can be rotated and min_decryption_version moved forward to ensure this data cannot be decrypted. This means that the web application can periodically change the encryption key used to encrypt the data, and set a minimum decryption version for the key, which prevents older versions of the key from being used to decrypt the data. This way, even if the attacker somehow obtained an old version of the key, they would not be able to decrypt the data that was encrypted with a newer version of the key.

The other statements are not true, because:

You cannot rotate the encryption key so that the attacker won't be able to decrypt the data. Rotating the key alone does not prevent the attacker from decrypting the data, as they may still have access to the old version of the key that was used to encrypt the data. You need to also move the min_decryption_version forward to invalidate the old version of the key.

The Vault administrator would not need to seal the Vault server immediately. Sealing the Vault server would make it inaccessible to both the attacker and the legitimate users, and would require unsealing it with the unseal keys or the recovery keys. Sealing the Vault server is a last resort option in case of a severe compromise or emergency, and is not necessary in this scenario, as the attacker does not have access to the encryption key or the data in Vault.Reference:Transit - Secrets Engines | Vault | HashiCorp Developer,Encryption as a service: transit secrets engine | Vault | HashiCorp Developer

Vault policies are written in HCL or JSON format and are attached to tokens or roles by name. Policies define the permissions and restrictions for accessing and performing operations on certain paths and secrets in Vault.Policies are deny by default, which means that an empty policy grants no permission in the system, and any request that is not explicitly allowed by a policy is implicitly denied1. Some of the features and benefits of Vault policies are:

Policies are path-based, which means that they match the request path to a set of rules that specify the allowed or denied capabilities, such as create, read, update, delete, list, sudo, etc2.

Policies are additive, which means that if a token or a role has multiple policies attached, the effective policy is the union of all the individual policies.The most permissive capability is granted if there is a conflict3.

Policies can use glob patterns, such as * and +, to match multiple paths or segments with a single rule.For example, path ''secret/*'' matches any path starting with secret/, and path ''secret/+/config'' matches any path with two segments after secret/ and ending with config4.

Policies can use templating to interpolate certain values into the rules, such as identity information, time, randomness, etc.For example, path ''secret/{{identity.entity.id}}/*'' matches any path starting with secret/ followed by the entity ID of the requester5.

Policies can be managed by using the vault policy commands or the sys/policy API endpoints.You can write, read, list, and delete policies by using these interfaces6.

The default policy is a built-in policy that is attached to all tokens by default and cannot be deleted. However, the default policy can be modified by using the vault policy write command or the sys/policy API endpoint.The default policy provides common permissions for tokens, such as renewing themselves, looking up their own information, creating and managing response-wrapping tokens, etc7.

You do not have to use YAML to define policies, as Vault supports both HCL and JSON formats.HCL is a human-friendly configuration language that is also JSON compatible, which means that JSON can be used as a valid input for policies as well8.

Vault does not need to be restarted in order for a policy change to take effect, as policies are stored and evaluated in memory. Any change to a policy is immediately reflected in the system, and any token or role that has that policy attached will be affected by the change.