CVE-2023-54397
Published:September 15, 2026
Updated:September 22, 2026
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.
Affected Packages
tornado (CONDA):
Affected version(s) >=2.3 <6.3.3Fix Suggestion:
Update to version 6.3.3https://github.com/tornadoweb/tornado.git (GITHUB):
Affected version(s) >=v1.0.0 <v6.3.3Fix Suggestion:
Update to version v6.3.3tornado (PYTHON):
Affected version(s) >=0.2 <6.3.3Fix Suggestion:
Update to version 6.3.3Related Resources (2)
Do you need more information?
Contact UsCVSS v4
Base Score:
9
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
LOW
Subsequent System Integrity
HIGH
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
LOW
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
EPSS
Base Score:
0.37