Cross-site Scripting (XSS) Affecting python-tornado package, versions *


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.04% (11th percentile)

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  • Snyk IDSNYK-DEBIAN13-PYTHONTORNADO-14407454
  • published13 Dec 2025
  • disclosed12 Dec 2025

Introduced: 12 Dec 2025

NewCVE-2025-67724  (opens in a new tab)
CWE-79  (opens in a new tab)
CWE-644  (opens in a new tab)

How to fix?

There is no fixed version for Debian:13 python-tornado.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-tornado package and not the python-tornado package as distributed by Debian. See How to fix? for Debian:13 relevant fixed versions and status.

Tornado is a Python web framework and asynchronous networking library. In versions 6.5.2 and below, the supplied reason phrase is used unescaped in HTTP headers (where it could be used for header injection) or in HTML in the default error page (where it could be used for XSS) and can be exploited by passing untrusted or malicious data into the reason argument. Used by both RequestHandler.set_status and tornado.web.HTTPError, the argument is designed to allow applications to pass custom "reason" phrases (the "Not Found" in HTTP/1.1 404 Not Found) to the HTTP status line (mainly for non-standard status codes). This issue is fixed in version 6.5.3.

CVSS Base Scores

version 3.1