The OWASP Top 10 — explained for business owners
The OWASP Top 10 is the industry-standard list of the most critical security risks to web applications, maintained by the Open Web Application Security Project. These are the vulnerabilities that attackers exploit most frequently — and the ones that cause the most damage when left unpatched.
1. Broken Access Control
When your application doesn't properly enforce who can access what. An attacker might be able to view other users' data, access admin panels, or modify records they shouldn't have permission to touch.
Real-world impact: A customer can change a URL parameter and view another customer's invoices, personal details, or account information.
How to prevent it: Enforce access controls on the server side. Never rely on hiding URLs or buttons — verify permissions on every request.
2. Cryptographic Failures
When sensitive data isn't properly encrypted — in transit (between the browser and server) or at rest (stored in databases). This includes using outdated encryption algorithms, storing passwords in plain text, or transmitting data without HTTPS.
Real-world impact: Customer passwords, credit card numbers, or personal information intercepted or stolen from the database.
How to prevent it: Use HTTPS everywhere, encrypt sensitive data at rest, hash passwords with strong algorithms (bcrypt/argon2), and avoid storing sensitive data you don't need.
3. Injection
When untrusted data is sent to an interpreter as part of a command or query. The most common form is SQL injection, where an attacker inserts database commands through form fields or URL parameters.
Real-world impact: An attacker enters malicious code in a login form and gains access to your entire database — customer records, passwords, payment information.
How to prevent it: Use parameterised queries for all database operations. Never build SQL statements by concatenating user input.
4. Insecure Design
Fundamental design flaws that can't be fixed by better implementation. This includes missing security controls, business logic that can be manipulated, and systems designed without considering how they might be abused.
Real-world impact: A discount code system that doesn't limit usage allows an attacker to apply the same code thousands of times.
How to prevent it: Include threat modelling in the design phase. Ask "how could someone abuse this?" for every feature.
5. Security Misconfiguration
Default settings, unnecessary features enabled, error messages revealing internal details, missing security headers, or overly permissive cloud storage buckets.
Real-world impact: An S3 bucket with public access exposes thousands of customer documents. A default admin password is never changed.
How to prevent it: Harden all configurations, disable unnecessary features, use security headers, and regularly audit settings.
6. Vulnerable and Outdated Components
Using software libraries, frameworks, or plugins with known security vulnerabilities. This is the single most common issue on WordPress sites — outdated plugins with published exploits.
Real-world impact: An outdated WordPress plugin allows an attacker to upload malicious files and take complete control of the website.
How to prevent it: Keep all software updated. Monitor for security advisories. Remove plugins and dependencies you don't actively use.
7. Identification and Authentication Failures
Weak authentication mechanisms — permitting weak passwords, not implementing multi-factor authentication, exposing session tokens, or failing to properly invalidate sessions on logout.
Real-world impact: An attacker brute-forces a weak admin password and gains full access to your CMS, customer data, and website content.
How to prevent it: Enforce strong passwords, implement MFA, rate-limit login attempts, and properly manage sessions.
8. Software and Data Integrity Failures
When code and infrastructure don't verify the integrity of software updates, plugins, or data pipelines. This includes auto-updating from untrusted sources or running CI/CD pipelines without integrity verification.
Real-world impact: A compromised plugin update installs a backdoor on your website that sends customer data to attackers.
How to prevent it: Verify the integrity of all software updates. Use trusted sources. Review what updates contain before applying them.
9. Security Logging and Monitoring Failures
Not logging security-relevant events, not monitoring those logs, or not having an incident response process. Without logging, you can't detect attacks. Without monitoring, you can't respond to them.
Real-world impact: An attacker has been accessing your system for months, but you don't know because nothing was logged or monitored.
How to prevent it: Log authentication events, access control failures, and input validation failures. Monitor logs for anomalies. Have an incident response plan.
10. Server-Side Request Forgery (SSRF)
When an application fetches a remote resource without validating the user-supplied URL. An attacker can trick the server into making requests to internal systems that should be inaccessible from the outside.
Real-world impact: An attacker uses your server to access internal APIs, cloud metadata services, or other internal systems — potentially accessing credentials or sensitive configuration.
How to prevent it: Validate and sanitise all user-supplied URLs. Use allowlists for permitted destinations. Block requests to internal IP ranges.
How many of these affect your website?
RabbiiCo Studio's free Attack Surface Scan checks your website against these vulnerabilities and gives you a prioritised fix list. No obligation, no jargon.