HashiCorp Vault is a secrets management, encryption, and identity-based access tool used to securely store, manage, and control access to sensitive information such as passwords, API keys, tokens, certificates, and encryption keys.

🔑 Core Capabilities of Vault

1️⃣ Secrets Management

• Centralized store for sensitive credentials (DB passwords, API keys, SSH keys, etc.)
• Supports dynamic secrets: Vault can generate short-lived credentials for databases, cloud providers, or services on demand.

2️⃣ Data Encryption as a Service (EaaS)

• Provides encryption/decryption APIs so applications can encrypt data without managing encryption keys themselves.
• Supports key rotation and policies without changing application code.

3️⃣ Identity-Based Access

• Integrates with identity providers (LDAP, Kubernetes, AWS IAM, etc.) to authenticate users and apps.
• Enforces fine-grained access policies via HashiCorp’s policy language (HCL).

4️⃣ Secrets Leasing & Revocation

• All credentials have leases (time-to-live).
• Supports revoking individual secrets or entire trees of secrets immediately to reduce exposure.

5️⃣ Audit Logging

• Records every access and operation for compliance and security monitoring.

📌 Where Vault Is Used

• Cloud & Multi-Cloud Environments: Manage secrets across AWS, Azure, GCP consistently.
• Kubernetes: Dynamically inject secrets into pods using Vault Agent or CSI driver.
• DevOps/CI-CD Pipelines: Provide temporary secrets for builds, deployments, and automation.
• Zero Trust Architectures: Combine Vault with tools like Boundary for identity-driven, just-in-time access.

✅ Example Use Case

• Application needs a database password.
• App authenticates to Vault (using AppRole, JWT, or Kubernetes auth).
• Vault generates a dynamic, short-lived DB credential and returns it.
• Credential automatically expires or is revoked after TTL.

🔗 TL;DR

Vault is HashiCorp’s platform for securing secrets and sensitive data, offering:

• Centralized secret storage
• Dynamic credentials
• Encryption as a service
• Identity-based access control
• Audit logging

It’s widely used in DevOps, cloud-native, and security-first environments to implement least privilege and zero-trust security models.