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CVE-2023-54397 (GCVE-0-2023-54397)

Vulnerability from cvelistv5 – Published: 2026-09-15 15:17 – Updated: 2026-09-15 15:17
VLAI
Title
Tornado before 6.3.3 HTTP Request Smuggling via Content-Length
Summary
Tornado before 6.3.3 contains an HTTP request smuggling vulnerability due to improper parsing of Content-Length headers accepting non-standard characters. Attackers can send crafted HTTP requests with these characters to bypass proxy validation and smuggle requests when deployed behind certain proxies.
Severity
9 (Critical)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:L/SI:H/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
Impacted products
Vendor Product Version CPE status
tornadoweb tornado Affected: 0 , < 6.3.3 (semver)
Unaffected: 6.3.3 (semver)
    cpe:2.3:a:tornadoweb:tornado:*:*:*:*:*:*:*:*
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Date Public
2023-08-12 00:00
Credits
kenballus
Show details on NVD website
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}



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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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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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