Attack Surface: Vault Server Vulnerabilities
Description: Exploitation of known security vulnerabilities in the Vault server software itself.
- Vault Contribution: Vault server software, like any software, can have vulnerabilities that attackers can exploit.
- Example: A known RCE vulnerability in a specific version of Vault allows an unauthenticated attacker to execute arbitrary code on the Vault server.
- Impact: Full compromise of the Vault server, including access to all secrets, audit logs, and potential control over the infrastructure.
- Risk Severity: Critical
- Mitigation Strategies:
- Regularly patch Vault server to the latest stable version.
- Implement vulnerability scanning of the Vault server infrastructure.
- Follow Vault security hardening guidelines and best practices.
Attack Surface: Vault API Exposure
Description: Direct exposure of the Vault API to untrusted networks without proper access controls.
- Vault Contribution: Vault exposes an API for management and secret retrieval, which if not properly secured, becomes an attack vector.
- Example: Vault API listener is exposed to the public internet without authentication. An attacker can enumerate API endpoints and attempt to exploit vulnerabilities or brute-force authentication.
- Impact: Unauthorized access to Vault secrets, potential data breaches, and possible control over Vault configurations.
- Risk Severity: High
- Mitigation Strategies:
- Isolate Vault server within a private network and restrict access to only authorized networks.
- Enforce HTTPS for all Vault API communication.
- Implement strong authentication methods for API access (tokens, TLS certificates, cloud provider IAM).
- Consider using an API Gateway or Web Application Firewall (WAF) to protect the Vault API.
Attack Surface: Authentication Method Misconfiguration
Description: Misconfiguration or vulnerabilities in Vault's authentication methods, leading to unauthorized access.
- Vault Contribution: Vault offers various authentication methods. Misconfiguring these methods can weaken security.
- Example: LDAP authentication is configured with weak binding credentials or without TLS, allowing an attacker to intercept credentials or bypass authentication.
- Impact: Unauthorized access to Vault, potentially leading to secret leakage and system compromise.
- Risk Severity: High
- Mitigation Strategies:
- Choose strong and secure authentication methods (TLS certificates, cloud provider IAM, OIDC/OAuth 2.0).
- Carefully configure authentication methods following security best practices and documentation.
- Regularly review and audit authentication method configurations.
- Apply the principle of least privilege to authentication capabilities.
Attack Surface: Policy Misconfigurations
Description: Overly permissive or incorrectly configured Vault policies granting excessive access to secrets.
- Vault Contribution: Vault's policy engine controls access to secrets. Misconfigured policies can lead to unintended access.
- Example: A policy grants read access to all secrets in the
secret/path to an application that only needs access to a specific secret. If the application is compromised, the attacker gains access to more secrets than necessary. - Impact: Increased blast radius of a compromise, potentially exposing more secrets than intended if an application or user is compromised.
- Risk Severity: High
- Mitigation Strategies:
- Design policies based on the principle of least privilege, granting only the minimum necessary access.
- Regularly review and audit Vault policies.
- Thoroughly test policies before deployment.
- Implement policy versioning and change management.
Attack Surface: Secret Engine Vulnerabilities
Description: Vulnerabilities or misconfigurations in specific Vault secret engines.
- Vault Contribution: Vault's secret engines generate and manage secrets. Vulnerabilities in these engines can expose secrets.
- Example: A vulnerability in a specific version of the database secret engine allows an attacker to bypass access controls and retrieve database credentials.
- Impact: Leakage of secrets managed by the vulnerable secret engine, potentially leading to compromise of downstream systems.
- Risk Severity: High
- Mitigation Strategies:
- Keep secret engines updated to the latest versions.
- Securely configure secret engines following best practices.
- Conduct engine-specific security reviews.
Attack Surface: Plugin Vulnerabilities (if using custom plugins)
Description: Vulnerabilities in custom Vault plugins or use of malicious plugins.
- Vault Contribution: Vault's plugin architecture allows for extensibility, but custom plugins can introduce new attack surfaces if not properly secured.
- Example: A custom authentication plugin has a vulnerability that allows authentication bypass. An attacker can exploit this plugin to gain unauthorized access to Vault.
- Impact: Potential compromise of Vault server or access to secrets, depending on the plugin's functionality and vulnerabilities.
- Risk Severity: High to Critical
- Mitigation Strategies:
- Follow secure coding practices for custom plugin development.
- Conduct thorough security audits and penetration testing of custom plugins.
- Implement a process for validating and verifying plugin security.
- Apply the principle of least privilege for plugin permissions.
- Avoid using unnecessary custom plugins.