CVE-2025-67724

MEDIUM EPSS 8.3%
Published Dec 12, 20256mo ago · Modified Jun 17, 20261w ago
6.1 CVSS 3.1
Medium
Find Similar
Published Dec 12, 2025 6mo ago
Last Modified Jun 17, 2026 1w ago

Description

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 Details

Base Score
6.1
Exploitability
2.8
Impact
2.7
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction Required
Scope Changed
Confidentiality Low
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
8.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 2

CWE-644
CWE-79 Cross-site Scripting Injection

Affected Products 1

VendorProductVersionRange
tornadowebtornado* <6.5.3

References 3

  • github.com https://github.com/tornadoweb/tornado/commit/9c163aebeaad9e6e7d28bac1f33580eb00b0e421
    Patch
  • github.com https://github.com/tornadoweb/tornado/releases/tag/v6.5.3
    Release Notes
  • github.com https://github.com/tornadoweb/tornado/security/advisories/GHSA-pr2v-jx2c-wg9f
    MitigationVendor Advisory

Remediation

  • github.com https://github.com/tornadoweb/tornado/commit/9c163aebeaad9e6e7d28bac1f33580eb00b0e421
    Patch