CVE-2026-66752

Publication date 28 July 2026

Last updated 7 August 2026

Ubuntu priority

Cvss 3 Severity Score

Description

tiny-http through 0.12.0 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize request framing by sending a Transfer-Encoding header with any value, including non-chunked codings, which causes the library to unconditionally apply chunk-decoding and discard Content-Length. Attackers can exploit the discrepancy between tiny_http's improper Transfer-Encoding parsing and a correctly-implemented front-end proxy to produce two distinct interpretations of a single byte stream, enabling request smuggling, and can additionally send non-chunked bodies with non-chunked Transfer-Encoding values to cause failed body reads that tie up connections and consume worker threads without signaling errors to clients.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
rust-tiny-http	26.04 LTS resolute	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Not in release

Severity score breakdown

CVSS version:

Base score 6.3 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	Present
Privileges required	None
User interaction	None
Vulnerable system - Confidentiality impact	None
Vulnerable system - Integrity impact	Low
Vulnerable system - Availability impact	Low
Subsequent system - Confidentiality impact	None
Subsequent system - Integrity impact	Low
Subsequent system - Availability impact	Low

Scores

Parameter	Value
Base score	6.3 · Medium
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:L/SA:L

Base score 5.4 · Medium