CVE-2023-54397

CVSS 9.0 (critical) · published 2026-09-15

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.

Weakness: CWE-444

Source: NVD CVE-2023-54397

References

• https://github.com/tornadoweb/tornado/security/advisories/GHSA-qppv-j76h-2rpx
• https://www.vulncheck.com/advisories/tornado-before-6.3.3-http-request-smuggling-via-content-length

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