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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.","publishedAt":"2026-07-28T15:44:41.573Z","updatedAt":"2026-08-14T16:50:45.981Z","severity":{"score":6.3,"label":"Medium","version":"4.0","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","source":"VulnCheck"},"assigner":"VulnCheck","products":["tiny-http tiny-http"],"affected":[{"vendor":"tiny-http","product":"tiny-http","packageURL":"pkg:github/tiny-http/tiny-http","defaultStatus":"affected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"0.12.0","versionType":"semver"}],"repo":"https://github.com/tiny-http/tiny-http"}],"references":["https://github.com/theopaid/HTTP-Request-Smuggling-via-Unparsed-Transfer-Encoding-Values-tiny_http-/tree/master","https://www.vulncheck.com/advisories/tiny-http-http-request-smuggling-via-transfer-encoding-handling"],"weaknesses":["CWE-444"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/66xxx/CVE-2026-66752.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-66752","state":"PUBLISHED","datePublished":"2026-07-28T15:44:41.573Z","dateUpdated":"2026-08-14T16:50:45.981Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-07-27T16:27:47.648Z"},"containers":{"cna":{"title":"tiny-http 0.12.0 HTTP Request Smuggling via Transfer-Encoding Handling","descriptions":[{"lang":"en","value":"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. 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