Vulnerability Description
Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, auth_username, auth_password, and auth_mode in place when a redirect changed scheme, host, or port. This issue is fixed in version 6.5.6.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/tornadoweb/tornado/commit/aba2569f7ed7a6bdbef816658fb6b718253
- https://github.com/tornadoweb/tornado/pull/3626
- https://github.com/tornadoweb/tornado/releases/tag/v6.5.6
- https://github.com/tornadoweb/tornado/security/advisories/GHSA-3x9g-8vmp-wqvf
FAQ
What is CVE-2026-49853?
CVE-2026-49853 is a vulnerability with a CVSS score of 7.7 (HIGH). Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization,...
How severe is CVE-2026-49853?
CVE-2026-49853 has been rated HIGH with a CVSS base score of 7.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-49853?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.