CVE-2023-54397
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.
Scoring
- Severity
- CRITICAL
- CVSS base score
- 9
- CVSS vector
- 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
- EPSS probability
- 0.37%
- CWE
- CWE-444
- Published
- 2026-09-15
- Last modified
- 2026-09-17
Affected products
- tornadoweb tornado
- tornadoweb tornado
Weakness type
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