threat-modeling.md

Threat Model Analysis for stackexchange/dnscontrol

Threat: Exposure of Sensitive Information in Configuration Files

• Description: An attacker gains unauthorized access to dnscontrol configuration files (e.g., dnsconfig.js) by compromising a repository, system, or backup. They then extract sensitive information like DNS provider API keys, internal domain names, or infrastructure details. This allows them to potentially take over DNS management or gain insights into the target infrastructure.
• Impact: Unauthorized access to DNS provider accounts, malicious DNS record modifications leading to hijacking or denial of service, information disclosure about infrastructure, potential for further system compromise.
• Affected dnscontrol component: Configuration Files (dnsconfig.js, dnsconfig.yaml)
• Risk Severity: High
• Mitigation Strategies:
  • Store configuration files in private repositories with strict access control.
  • Utilize environment variables or secrets management systems to inject sensitive credentials instead of hardcoding them.
  • Regularly review configuration files for accidentally committed secrets.
  • Implement file system permissions to restrict access to configuration files on systems where dnscontrol is executed.
  • Encrypt configuration files at rest if possible.

Threat: Malicious Modification of Configuration Files

• Description: An attacker with access to configuration files (e.g., through repository compromise or system access) modifies them to manipulate DNS records. This could involve changing IP addresses to redirect traffic to malicious servers, modifying MX records for email interception, or deleting records to cause denial of service. The attacker leverages dnscontrol's configuration-driven approach to automate widespread DNS changes.
• Impact: DNS hijacking leading to phishing or malware distribution, redirection to malicious websites, denial of service causing website and service unavailability, email spoofing and interception, significant reputational damage and financial loss.
• Affected dnscontrol component: Configuration Files (dnsconfig.js, dnsconfig.yaml)
• Risk Severity: Critical
• Mitigation Strategies:
  • Implement strong access control to the repository and systems where configuration files are stored and processed.
  • Use version control (like Git) to track changes to configuration files and enable rollback to previous versions.
  • Implement mandatory code review processes for all changes to dnscontrol configurations.
  • Consider using signed commits to verify the integrity of configuration changes.
  • Implement monitoring and alerting for unexpected DNS changes to detect unauthorized modifications quickly.

Threat: Hardcoded Credentials in Scripts or Configuration

• Description: Developers inadvertently hardcode DNS provider API keys or secrets directly into dnscontrol scripts, custom modules, or even within comments in configuration files. An attacker who gains access to these files (e.g., through code repository access or system compromise) can easily extract these credentials.
• Impact: Credential exposure granting full or partial control over DNS provider accounts, unauthorized access to modify DNS records leading to hijacking or denial of service, potential for further exploitation of the compromised DNS provider account.
• Affected dnscontrol component: Scripts, Custom Modules, Configuration Files
• Risk Severity: High
• Mitigation Strategies:
  • Strictly avoid hardcoding credentials in any part of the dnscontrol configuration or related scripts.
  • Mandate the use of environment variables or dedicated secrets management solutions (like HashiCorp Vault, AWS Secrets Manager, etc.) for managing and injecting credentials.
  • Implement automated code scanning tools to detect potential hardcoded secrets in scripts and configuration files during development and CI/CD pipelines.
  • Conduct regular security code reviews to manually inspect for potential hardcoded credentials.

Threat: Insecure Storage of Credentials

• Description: Even when not hardcoded, if credentials used by dnscontrol are stored insecurely on the system where dnscontrol runs (e.g., in plain text files, easily accessible locations, or weakly protected storage), they become vulnerable to compromise. An attacker gaining system access can easily retrieve these credentials.
• Impact: Credential exposure leading to unauthorized access to DNS provider accounts, malicious DNS record modifications causing hijacking or denial of service, potential for broader compromise if the same credentials are reused elsewhere.
• Affected dnscontrol component: Credential Management, Execution Environment
• Risk Severity: High
• Mitigation Strategies:
  • Mandatory use of secure secrets management systems to store and retrieve credentials used by dnscontrol.
  • Ensure proper file system permissions on any files containing credentials (even encrypted ones) to restrict access to authorized users and processes only.
  • Implement regular rotation of DNS provider API keys to limit the window of opportunity if credentials are compromised.
  • Encrypt credential storage at rest and in transit if file-based storage is unavoidable, using strong encryption algorithms and key management practices.

Threat: Insufficient Access Control to dnscontrol Execution Environment

• Description: If access to the systems where dnscontrol is executed (e.g., CI/CD servers, administrative workstations) is not properly restricted, unauthorized users or compromised systems could run dnscontrol commands. This allows them to make unintended or malicious DNS changes, bypassing intended authorization workflows.
• Impact: Unauthorized DNS modifications leading to service disruption or hijacking, potential for data breaches if DNS is used for service discovery or access control, reputational damage and loss of trust.
• Affected dnscontrol component: Execution Environment, CLI Interface
• Risk Severity: High
• Mitigation Strategies:
  • Implement strong multi-factor authentication and authorization mechanisms for accessing systems where dnscontrol is run.
  • Enforce role-based access control (RBAC) to strictly limit who can execute dnscontrol commands and what actions they are permitted to perform.
  • Apply the principle of least privilege, granting only the necessary permissions to users and processes interacting with dnscontrol.
  • Regularly audit user access and permissions to the dnscontrol execution environment and revoke unnecessary access.

Threat: Accidental Misconfiguration Leading to DNS Outages

• Description: Human error during the creation or modification of dnscontrol configuration files can introduce incorrect DNS records. When dnscontrol applies these configurations, it can lead to widespread DNS resolution failures, making websites and services inaccessible. This highlights the risk of declarative configuration if not carefully managed.
• Impact: Website and service unavailability causing business disruption, email delivery failures, negative impact on customer experience and revenue, potential damage to brand reputation.
• Affected dnscontrol component: Configuration Files, CLI Interface, Apply Functionality
• Risk Severity: High
• Mitigation Strategies:
  • Implement mandatory and thorough testing of all dnscontrol configurations in non-production staging or testing environments before applying them to production.
  • Always utilize the dry-run mode of dnscontrol to preview and carefully review all proposed changes before executing the actual apply command.
  • Implement comprehensive DNS monitoring and alerting to quickly detect and remediate any DNS resolution issues caused by misconfigurations.
  • Establish and regularly test rollback procedures to rapidly revert to previous known-good DNS configurations in case of accidental misconfigurations or errors.
  • Implement mandatory code review processes for all dnscontrol configuration changes to catch potential errors before deployment.

Threat: Denial of Service through DNS Record Manipulation

• Description: An attacker who successfully gains unauthorized access to dnscontrol (through compromised credentials, configuration access, or vulnerabilities) can intentionally manipulate DNS records to disrupt services. This could involve pointing critical domains to non-existent or incorrect IPs, deleting essential records, or creating conflicting records, effectively causing a denial of service.
• Impact: Complete service outages and website unavailability, preventing users from accessing online services, significant business disruption and financial losses, reputational damage, potential loss of customer trust.
• Affected dnscontrol component: Apply Functionality, DNS Provider Interaction
• Risk Severity: Critical
• Mitigation Strategies:
  • Implement robust access control and credential management measures as previously described to prevent unauthorized access to dnscontrol.
  • Implement real-time monitoring and alerting for any unexpected or unauthorized DNS changes to detect and respond to malicious activity promptly.
  • Consider implementing rate limiting or anomaly detection mechanisms on DNS changes applied through dnscontrol to identify and block suspicious bulk modifications.
  • Explore and implement DNSSEC (Domain Name System Security Extensions) to cryptographically sign DNS records, protecting against DNS spoofing and tampering (although dnscontrol itself doesn't directly introduce vulnerabilities related to DNSSEC, it's a crucial mitigation in the broader DNS security context).