Overview
APIs have emerged as the primary attack vector for enterprise cybersecurity threats, surpassing ransomware and phishing as critical concerns. According to a Gartner report from October 2022, API attacks represent the most common threat to enterprise web applications. The scale of this crisis is staggering:
- API attack traffic increased 681% in 2021 (Gartner prediction now realized)
- Malicious API traffic grew 348% while overall API traffic increased 141% (Salt Security, 2021)
- 94% of organizations experienced API security problems in production APIs within 12 months (Salt Labs, August 2022)
- 20% of respondents suffered data breaches resulting from API security gaps (Salt Labs, August 2022)
- 77% of retail respondents experienced API security incidents in 2021 (Noname Security)
- API attack traffic doubled in 12 months preceding August 2022 (Salt Labs)
Key Threats
OWASP API Security Top 10 Vulnerabilities
Organizations must understand and defend against the vulnerabilities outlined in the OWASP API Security Top 10 framework. The most critical threats include:
1. Broken Access Control (Broken Function Level Authorization) Access control flaws remain among the highest-severity exploited vulnerabilities. In Q1 2022, broken access controls were the most dangerous, exploited API vulnerabilities disclosed (Wallarm, August 2022). A critical example occurred when Salt Security discovered a Server-Side Request Forgery (SSRF) vulnerability on a US-based FinTech platform (April 2022) that could have enabled administrative account takeover (ATO). This vulnerability could have: - Granted attackers administrative access to banking systems - Exposed users' banking details and financial transactions - Leaked personal data to threat actors - Enabled unauthorized funds transfers
2. Injection Attacks Injection attacks ranked as the second most critical API threat in Q1 2022 disclosures (Wallarm). These attacks exploit insufficient input validation.
3. Business Logic Flaws Unlike traditional vulnerabilities, business logic flaws are invisible to automated scanning tools and specific to each organization's context. Attackers exploit inherent design and implementation flaws to: - Manipulate legitimate data and workflows - Perform privilege escalation - Execute account takeovers - Scrape sensitive data
Notable example: Facebook's API logic flaw that exposed tens of millions of user records resulted from unauthorized API use and business logic exploitation (2023).
4. Excessive Data Exposure Concerns about privacy, data leakage, and object property exposure with internal or external-facing APIs were reported by almost 50% of respondents (Cloudentity State of API Security report cited in November 2021 OWASP article).
5. Other Critical Issues - Cryptographic failures - Insecure design - Misconfigurations
Why APIs Are Attractive Targets
- Authentication Bypass: Most API attacks occur within authenticated and authorized sessions, meaning attackers don't need to breach access controls—they exploit functionality post-authentication
- Low Detection Rate: Traditional security systems and web application firewalls fail to detect API-specific attacks
- Expanding Attack Surface: 73% of enterprises reported publishing more than 50 APIs in 2021, creating massive security gaps
- Lack of Awareness: General lack of security awareness makes APIs "low-effort, high-reward" targets (Salt Security CEO Roey Eliyahu, July 2021)
- Inadequate Testing: Many APIs lack rigorous security testing before production deployment
Notable Incidents
FinTech Platform Critical SSRF (April 2022) - Vulnerability: Server-Side Request Forgery (SSRF) - Impact: Could enable administrative account takeover on platform serving hundreds of banks and millions of customers - Potential: Access to all user accounts and transaction data - Status: Remediated after coordinated disclosure by Salt Labs
Historical Major Breaches - Equifax (2017): API breach exposed 147 million accounts - Facebook: Tens of millions of user records exposed via API logic flaw - Experian, Geico, Peloton: Additional API-related breaches reported (2021)
Q1 2022 Vulnerability Disclosures (Wallarm Report) - 48 total API-related vulnerabilities found - 18 classified as high-risk - 19 labeled medium severity - CVSS v3 scores ranged from 8.1 to 10.0 - CVE-2022-26501 (CVSS 9.8) represents critical-severity access control flaws
Recommendations
Strategic Approach
- Move Beyond Perimeter Security
- API gateways alone are insufficient for comprehensive API security
- Implement sophisticated techniques beyond conventional API gateway functionality
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API gateways provide core functionality but cannot address emerging business logic and context-specific vulnerabilities
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Implement Production Monitoring
- Shift-left strategies focused solely on development phases are failing (Salt Labs finding)
- Deploy runtime detection and monitoring for production APIs
- Identify vulnerabilities proactively from production back to code
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73% of enterprises publish 50+ APIs; production visibility is critical
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Address Business Logic Flaws
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Since business logic flaws are invisible to automated scanning tools, implement:
- Manual security code reviews by threat-aware engineers
- Behavioral analysis of API usage patterns
- Context-specific penetration testing
- Red team exercises focused on business logic exploitation
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Leverage Training and Testing Platforms
- Deploy vAPI (Vulnerable Adversely Programmed Interface), an open-source PHP-based lab environment that mimics OWASP API Top 10 vulnerabilities
- Use platforms available on GitHub, operable via PHP, MySQL, and Postman, or Docker
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Train security professionals and developers on API attack vectors
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Implement OWASP API Security Top 10 Controls
- Enforce broken access control fixes through:
- Role-based access control (RBAC)
- Principle of least privilege
- Function-level authorization checks
- Deploy input validation and output encoding to prevent injection attacks
- Implement rate limiting and DDoS protection
- Enforce encryption for data in transit and at rest
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Implement comprehensive logging and monitoring
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Organizational Measures
- Make API security a primary consideration within broader enterprise cybersecurity strategies
- Prioritize API security in DevOps pipelines despite production velocity pressures
- Allocate resources to API security teams (many report feeling ill-prepared and overwhelmed)
- Establish coordinated disclosure practices for vulnerability management
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Implement security awareness programs addressing the general lack of API security knowledge
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Technical Controls
- Require security testing from development through production
- Implement server-side request forgery (SSRF) protections
- Deploy Web Application Firewalls (WAF) with API-specific rules
- Use identity and access management (IAM) solutions specifically tuned for API authentication
- Monitor for unauthorized API usage within authenticated sessions
Timeline Consideration
Organizations report slowing or halting production releases due to API security concerns, negatively impacting digital transformation and DevOps initiatives. The urgency is amplified by projections that by 2023, over 50% of B2B transactions will be performed via real-time APIs, expanding the attack surface and potential impact of breaches.
Source: CyberBriefing intelligence synthesis from 20 years of historical threat data.