CyberCertPrepWeb App FundamentalsHTTP & Web BasicsEASYFree question
An analyst sees a POST request body with 'application/x-www-form-urlencoded' encoding: 'name=John+Doe&amount=100%2E00'. What does '%2E' represent?
- A.It is a reserved marker (used in several legacy form parsers written before RFC 1866) for control characters below 0x20
- B.A percent-encoded period (.) character - URL encoding replaces non-alphanumeric characters with % followed by their two-digit hex ASCII code
- C.It represents a checksum byte (appended by some legacy form parsers for integrity checking) after each numeric field value
- D.It marks a locale-specific decimal separator (common in some European browser configurations) before submission
Why B is correct
URL encoding (percent-encoding) converts characters to their hexadecimal ASCII representation preceded by %. %2E is the encoding for '.' (period, ASCII 0x2E). '+' encodes space in form data. Security relevance: servers must properly decode URL-encoded input before processing, and security filters must decode values before inspecting them - otherwise attackers can bypass filters using encoded versions of dangerous characters.
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