CVE-2026-54387
Critical · CVSS 9.1Tinyproxy — HTTP Request Smuggling via CL-TE (Content-Length / Transfer-Encoding) desynchronization
- CVSS
- 9.1
- nvd
- EPSS
- —
- KEV
- No
- Class
- oss containerizable
- CWE-444
Description
Tinyproxy through 1.11.3, fixed in commit ff45d3b, fails to reconcile conflicting Content-Length and Transfer-Encoding: chunked headers, forwarding both verbatim to the backend while using Content-Length to determine how many request body bytes to consume. Remote attackers can desynchronize the proxy and backend parser state, allowing injection of arbitrary HTTP requests to the backend to enable cache poisoning, access control bypass, and request hijacking.
Search profile — drives PoC discovery
Symbols Content-LengthTransfer-Encodingchunkedff45d3bf0e61d0f8ed97ab379d3047f04eb67521handle_requestread_request_bodytinyproxy.confReqWriteTimeoutMaxClients
Keywords CVE-2026-54387TinyproxyHTTP request smugglingCL-TE desynchronizationContent-Length Transfer-Encodingcache poisoningaccess control bypassrequest hijackingtinyproxy 1.11.3CWE-444proxy desync
Versions: through 1.11.3 (fixed in commit ff45d3b)
References
Status: enriched · ingested 2026-07-15T00:00:20.000Z · profiled 2026-07-15T00:30:20.000Z