CVE-2026-54387 (GCVE-0-2026-54387)

Vulnerability from cvelistv5 – Published: 2026-06-17 19:48 – Updated: 2026-06-18 13:10 X_Open Source
VLAI
Title
Tinyproxy - HTTP Request Smuggling via CL/TE Desynchronization
Summary
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.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
Impacted products
Vendor Product Version
tinyproxy tinyproxy Affected: 0 , ≤ 1.11.3 (semver)
Unaffected: ff45d3bf0e61d0f8ed97ab379d3047f04eb67521 (git)
Create a notification for this product.
Date Public
2026-05-07 00:00
Credits
Tristan Madani (@TristanInSec)
Show details on NVD website
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