HTTP Header Injection Affecting tornado package, versions [,6.5.3)
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Test your applications- Snyk IDSNYK-PYTHON-TORNADO-14400978
- published12 Dec 2025
- disclosed12 Dec 2025
- creditFinder16
Introduced: 12 Dec 2025
NewCVE-2025-67724 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade tornado to version 6.5.3 or higher.
Overview
tornado is a Python web framework and asynchronous networking library, originally developed at FriendFeed.
Affected versions of this package are vulnerable to HTTP Header Injection via the reason argument in HTTP status handling. An attacker can inject arbitrary HTTP headers or execute malicious scripts in the browser by supplying crafted input to the RequestHandler.set_status or tornado.web.HTTPError parameters.
##Workaround
This issue can be mitigated by controlling the usage of untrusted data for the reason argument.