{"cve":"CVE-2025-67724","nvd":{"published":"2025-12-12T06:15:41.213","modified":"2026-10-07T20:10:01.970","status":"Analyzed","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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79","CWE-644"],"references":["https://github.com/tornadoweb/tornado/commit/9c163aebeaad9e6e7d28bac1f33580eb00b0e421","https://github.com/tornadoweb/tornado/releases/tag/v6.5.3","https://github.com/tornadoweb/tornado/security/advisories/GHSA-pr2v-jx2c-wg9f"],"products":["tornadoweb:tornado"],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2025-67724","score":0.0024,"percentile":0.1496,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-pr2v-jx2c-wg9f","url":"https://osv.dev/vulnerability/GHSA-pr2v-jx2c-wg9f","summary":"Tornado vulnerable to Header Injection and XSS via reason argument","modified":"2026-07-20T19:00:24.953994999Z","packages":[{"ecosystem":"PyPI","name":"tornado","purl":"pkg:pypi/tornado","ranges":["<6.5.3"],"fixed":["6.5.3"]}]},{"id":"PYSEC-2025-265","url":"https://osv.dev/vulnerability/PYSEC-2025-265","summary":"","modified":"2026-07-13T07:15:44.068555841Z","packages":[{"ecosystem":"PyPI","name":"tornado","purl":"pkg:pypi/tornado","ranges":["<6.5.3"],"fixed":["6.5.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}