CVE-2026-66752 (GCVE-0-2026-66752)

Vulnerability from cvelistv5 – Published: 2026-07-28 15:44 – Updated: 2026-08-14 16:50 X_Open Source
VLAI
Title
tiny-http 0.12.0 HTTP Request Smuggling via Transfer-Encoding Handling
Summary
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.
Severity
6.3 (Medium)
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
5.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-28 17:31 UTC
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6373 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
tiny-http tiny-http Affected: 0 , ≤ 0.12.0 (semver)
    cpe:2.3:a:tiny-http_project:tiny-http:*:*:*:*:*:node.js:*:*
Create a notification for this product.
Date Public
2026-07-26 00:00
Credits
Theodosis Paidakis
Show details on NVD website
To clipboard 

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