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Implement ESAPI.validator:ESAPI.validator().isValidFileName("context", filename, false)
Learn More:
OWASP Development Guide: Chapter on Configuration
OWASP Code Review Guide: Chapter on Error Handling
http://www.owasp.org/index.php/Error_HandlingOWASP Testing Guide: Configuration Management
OWASP Testing Guide: Testing for Error Codes
OWASP Top 10 2004 - Insecure Configuration Management
http://www.owasp.org/index.php/A10_2004_Insecure_Configuration_ManagementPC Magazine Article on Web Server Hardening