CVE-2026-66752 Details
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.
A request smuggling vulnerability has been identified in tiny-http versions prior to and including 0.12.0. This vulnerability arises because the library improperly parses the Transfer-Encoding header, allowing remote attackers to desynchronize request framing. By sending a Transfer-Encoding header with any value, including non-chunked codings, tiny-http unconditionally applies chunk-decoding and ignores the Content-Length header. This misinterpretation creates a discrepancy between tiny-http and correctly-implemented front-end proxies, enabling request smuggling. Additionally, attackers can exploit non-chunked bodies with non-chunked Transfer-Encoding values to cause failed body reads, tying up connections and consuming worker threads without notifying clients.
Users are advised to update to tiny-http versions that have addressed this vulnerability. As of now, there is no fixed version available.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jul 28, 2026CISA-ADP
Assessed Jul 28, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-444 | Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| tiny-http | <= 0.12.0 (semver) |
CPE
Remediation
| |
Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 28, 2026 | CVE Modified | CISA-ADP |
| Jul 28, 2026 | CVE Modified | [email protected] |
| Jul 28, 2026 | New CVE Received | [email protected] |