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.A null byte used for path traversal; an absolute-form request target is only legal when speaking to a proxy in HTTP/1.0, and HTTP/1.1 removed it; chunked transfer encoding is only legal in HTTP/2, where it replaces the DATA frame mechanism
- B.A percent-encoded period (.) character - URL encoding replaces non-alphanumeric characters with % followed by their two-digit hex ASCII code
- C.A Unicode escape sequence for the Euro sign; gzip content encoding is applied before TLS encryption specifically to defeat compression side channels like BREACH; HTTP redirects are capped at 3 hops by the specification, after which the browser must show the intermediate page
- D.An HTML entity reference for the ampersand
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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