CVE-2026-54388 (GCVE-0-2026-54388)

Vulnerability from cvelistv5 – Published: 2026-06-17 19:59 – Updated: 2026-06-18 15:33 X_Open Source
VLAI
Title
Tinyproxy - HTTP Request Smuggling via Duplicate Content-Length Headers
Summary
Tinyproxy through 1.11.3, fixed in commit 364cdb6, fails to reject requests containing multiple Content-Length headers with differing values, forwarding all duplicate headers to the backend while using the first value 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: poc 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: 364cdb67e0ea00a8e4a7037e2693e0711e816adb (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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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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