Http11Probe

TE-NULL

Test ID SMUG-TE-NULL
Category Smuggling
RFC RFC 9110 §5.5, RFC 9112 §6.1
Requirement MUST reject malformed field value
Expected 400 or close

What it sends

Transfer-Encoding: chunked<NUL> with Content-Length present.

POST / HTTP/1.1\r\n
Host: localhost:8080\r\n
Transfer-Encoding: chunked\x00\r\n
Content-Length: 5\r\n
\r\n
hello

Why it matters

NUL handling differences (truncate vs reject) are a classic parser differential that can destabilize message framing.

Sources

Http11Probe — HTTP/1.1 compliance & smuggling testerSource on GitHub