Checks for server info disclosure in HTTP headers
Detects server fingerprinting headers that may expose sensitive server information including software versions, technology stacks, and implementation details.
This checker examines HTTP response headers that commonly expose server fingerprinting information, which can be used by attackers to identify vulnerabilities and plan targeted attacks.
Server: Reveals web server software and version (e.g., "Apache/2.4.41", "nginx/1.18.0")
X-Powered-By: Exposes backend technology and version (e.g., "PHP/7.4.3", "ASP.NET")
X-AspNet-Version: Discloses .NET Framework version (e.g., "4.0.30319")
The checker uses regex pattern matching to identify version numbers in header values. Any sequence matching \d+(?:\.\d+)*(?:[-+][a-zA-Z0-9\-.]*)? is considered version information.
Remove or minimize server identification headers
Use generic values without version information
Configure web servers to suppress detailed software information
| Status | Condition | Description | Action Required |
|---|---|---|---|
| ✅ Success | No fingerprinting headers found | None of the monitored headers (Server, X-Powered-By, X-AspNet-Version) are present in the response | No action needed - Server is properly configured to minimize information disclosure |
| ⚠️ Warning | Headers present without version info | One or more fingerprinting headers are present but contain only generic information without version numbers | Recommended - Consider removing these headers entirely for maximum security |
| ❌ Failure | Headers contain version information | One or more headers expose specific version numbers, software details, or implementation information | Action required - Remove or sanitize headers to prevent information disclosure |
Success: No Server, X-Powered-By, or X-AspNet-Version headers
Warning: Server: Apache (no version), X-Powered-By: ASP.NET (no version)
Failure: Server: Apache/2.4.41, X-Powered-By: PHP/7.4.3, X-AspNet-Version: 4.0.30319
When server headers contain version information, attackers can:
Exploit Known Vulnerabilities: Target specific CVEs for the disclosed software versions
Launch Targeted Attacks: Craft attacks specific to the identified technology stack
Reconnaissance: Build detailed profiles of your infrastructure for advanced persistent threats
Compliance Issues: Violate security frameworks that require information disclosure minimization
Even without version info, server headers still provide:
Technology Fingerprinting: Help attackers identify the general technology stack
Attack Surface Mapping: Allow reconnaissance of potential entry points
Social Engineering: Enable more convincing phishing attempts targeting your tech stack
Increased vulnerability to targeted cyber attacks
Potential data breaches and system compromises
Regulatory compliance violations (GDPR, PCI-DSS, SOX)
Reputational damage from security incidents
Financial losses from downtime and remediation costs
Add this checker to your monitoring setup and start identifying issues on your websites today.