Vulnerability in tornadoweb tornado

[ Description ]Official 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.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund11 Oct 2026WID-SEC-2026-3870

  Red Hat Enterprise Linux (python-tornado): Multiple vulnerabilities Translated from German

  CVE-2026-91990CVE-2026-49855CVE-2026-49853

[ References ]References

• github.com/tornadoweb/tornado/security/advisories/GHSA-3x9g-8vmp-wqvfx_refsource_CONFIRM
• github.com/tornadoweb/tornado/pull/3626x_refsource_MISC
• github.com/tornadoweb/tornado/commit/aba2569f7ed7a6bdbef816658fb6b7182531b751x_refsource_MISC
• github.com/tornadoweb/tornado/releases/tag/v6.5.6x_refsource_MISC