Vulnerability record · CVE-2026-49853 · published 14 July 2026
CVE-2026-49853: Information exposure vulnerability
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.
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:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-49853), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.