Inconsistent interpretation of HTTP requests in Tornado - #VU128145
Published: June 6, 2024 / Updated: April 27, 2026
Vulnerability identifier: #VU128145
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-444
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform HTTP request smuggling.
The vulnerability exists due to inconsistent interpretation of HTTP requests in the Tornado HTTP request parser when processing requests with multiple Transfer-Encoding: chunked headers. A remote attacker can send a specially crafted request to perform HTTP request smuggling.
Exploitation requires Tornado to be deployed behind a proxy server that forwards requests containing multiple Transfer-Encoding: chunked headers.
Affected software
Tornado
Remediation
Install security update from vendor's website.
Tornado - update to 6.4.1