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CVE-2023-54397

Tornado before 6.3.3 HTTP Request Smuggling via Content-Length

CVSS 4.0 9.0 CRITICALCVSS 3.1 7.5 HIGHCheck source for fixed versionsKEV status unknown
Original advisory

cve-program · CVE-2023-54397

Published

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.

Read the publisher's advisory

Affected versions, risk and source history

Exploitation and risk

Source status

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cve-program · CVE-2023-54397

Published

Tornado before 6.3.3 HTTP Request Smuggling via Content-Length

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.

Source published
15 Sep 2026 15:17:52 UTC
Source modified
17 Sep 2026 14:48:55 UTC
Saved here
23 Oct 2026 15:48:27 UTC
Source terms
CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 4.0 · 9.0 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

CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N

ChangeIntel

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Sources read 13 Nov 07:12 UTC · 274 of 275 readable · 272 fully read · documentation 469/469 current

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