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Security9 min read

Web application security: the complete 2026 checklist

April 14, 2026·VirtuoLab

Why web security is essential

In 2025 more than 30,000 websites were hacked every day. A security hole can lead to data loss, reputational damage and fines under the GDPR.

The OWASP Top 10 (2026)

The OWASP Top 10 is the industry standard for the most critical security risks:

1Broken access control — users can perform actions they aren't authorised for
2Cryptographic failures — sensitive data stored or transmitted unencrypted
3Injection — SQL injection, XSS, command injection
4Insecure design — fundamental design flaws
5Security misconfiguration — default passwords, open cloud storage
6Vulnerable components — outdated libraries with known vulnerabilities
7Authentication failures — weak passwords, missing MFA
8Data integrity failures — insecure deserialisation, untrusted CI/CD
9Logging failures — insufficient monitoring and logging
10SSRF — Server-Side Request Forgery

The security checklist

Transport & encryption

HTTPS everywhere (SSL/TLS certificate)
HSTS header configured
Sensitive data encrypted in the database

Authentication & authorisation

Strong password requirements
Multi-factor authentication (MFA)
Rate limiting on login endpoints
Session management with secure cookies

Input validation

Server-side validation on all inputs
Parameterised queries (no string concatenation)
Content Security Policy header
XSS prevention (output encoding)

HTTP headers

X-Content-Type-Options: nosniff
X-Frame-Options: DENY
Referrer-Policy: strict-origin-when-cross-origin
Permissions-Policy

Monitoring

Error logging without sensitive data
Alerting on suspicious activity
Regular dependency audits

How VirtuoLab approaches security

Security is not an afterthought — it is built into our development process. From input validation to security headers: everything is included as standard. More about our approach.

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