Overview
Weaknesses in the interfaces that connect mobile apps to cloud services can be exploited by attackers. Insecure APIs (Application Programming Interfaces) occur when mobile apps communicate with cloud services or other external systems using poorly secured APIs. Common vulnerabilities in APIs include lack of authentication, improper input validation, and insufficient encryption. Attackers can exploit these flaws to intercept data, perform unauthorized actions, or gain access to backend systems. Since APIs often handle sensitive data or critical app functionality, securing APIs is crucial to mobile application security. APIs are a critical attack surface due to their role in handling sensitive data and business logic. Specific attack methods using insecure APIs include:
- Exploiting broken object-level authorization (BOLA) to access unauthorized resources
- Abusing insecure direct object references (IDOR) to manipulate data
- Stealing API keys or tokens due to poor storage or transmission practices
- Exploiting misconfigured CORS (Cross-Origin Resource Sharing) policies
Risk factors
Insecure APIs can arise from:
- APIs that do not require proper authentication or authorization to access resources
- APIs that do not properly validate or sanitize input, leaving them vulnerable to SQL injection, XSS, or other attacks
- APIs that do not limit the number of requests allowed in a specific timeframe, making them vulnerable to brute-force attacks
- Transmitting sensitive data via APIs without using encryption (e.g., HTTP instead of HTTPS)
- Lack of API versioning, which can expose deprecated or insecure endpoints
- Poorly protected API keys or tokens stored in client-side code or logs
Consequences
If an attacker successfully exploits insecure APIs, the following could happen:
- Unauthorized access: Attackers can gain access to backend systems or sensitive data by bypassing authentication or exploiting poorly secured endpoints.
- Data breach: Sensitive information, such as personal data, financial records, or API keys, could be stolen by attackers.
- Service disruption: Attackers may exploit APIs to disrupt app functionality or take services offline through denial-of-service (DoS) attacks.
- Data manipulation: Attackers can modify or delete data through exploited APIs, leading to data integrity issues or unauthorized changes.
Solutions and best practices
To mitigate the risks associated with insecure APIs, organizations should implement the following security measures:
- API authentication and authorization: Implement strong authentication and authorization mechanisms, such as OAuth 2.0, to secure API access.
- Input validation: Ensure that all inputs to APIs are properly validated and sanitized to prevent injection attacks or unauthorized actions.
- Rate limiting: Implement rate limiting to prevent brute-force attacks and DoS attempts on APIs.
- Use HTTPS: Ensure that all data transmitted between mobile apps and APIs is encrypted using HTTPS (TLS/SSL) to protect against eavesdropping and interception.
- App shielding: App shielding can add additional layers of protection by encrypting data, detecting tampering, and securing communication between apps and APIs.