CVE-2026-49853 | Tornado is a Python web framework and asynchronous networkin… | CVSS 7.7 HIGH

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.

Metadata

CVE ID: CVE-2026-49853
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-01 22:03 UTC
Published: 2026-07-14 20:41 UTC
Last updated: 2026-07-14 20:41 UTC
Primary CWE: CWE-200
CWE-200: Exposure of Sensitive Information to an Unauthorize…
Vendor / Product: tornadoweb / tornado
Sources: cve.org · NVD

Severity & Metrics

7.7 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

Affected products (1)

Vendor	Product	Platform	Versions
tornadoweb	tornado	—	< 6.5.6

Weakness (CWE)

CWE	Source	Description
CWE-200	cna	CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

CVSS scores (1)

Score	Severity	Version	Source	Vector
7.7	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

References (4)

https://github.com/tornadoweb/tornado/security/advisories/GHSA-3x9g-8vmp-wqvf https://github.com/tornadoweb/tornado/security/advisories/GHSA-3x9g-8vmp-wqvf
https://github.com/tornadoweb/tornado/pull/3626 https://github.com/tornadoweb/tornado/pull/3626
https://github.com/tornadoweb/tornado/commit/aba2569f7ed7a6bdbef816658fb6b7182531b751 https://github.com/tornadoweb/tornado/commit/aba2569f7ed7a6bdbef816658fb6b7182531b751
https://github.com/tornadoweb/tornado/releases/tag/v6.5.6 https://github.com/tornadoweb/tornado/releases/tag/v6.5.6