CVE-2026-49853

Tornado: Authorization header forwarded across cross-origin redirects in SimpleAsyncHTTPClient

Published Jul 14, 2026 CVSS 3.1 · 7.7 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-3x9g-8vmp-wqvf Tornado: Authorization header forwarded across cross-origin redirects in SimpleAsyncHTTPClient
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Tornadoweb
Tornadoweb tornado
Vendors & Products Tornadoweb
Tornadoweb tornado
Type Values Removed Values Added
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.
Title Tornado: Authorization header forwarded across cross-origin redirects in SimpleAsyncHTTPClient
Weaknesses CWE-200
References
Metrics cvssV3_1

{'score': 7.7, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 21, 2026, 2:47 PM
Reserved
Jun 1, 2026, 10:03 PM
Status
Deferred
Published
Jul 14, 2026, 9:17 PM
Modified
Oct 24, 2026, 9:10 PM