{"schema_version":"1.7.5","id":"GHSA-78cv-mqj4-43f7","published":"2026-03-11T22:17:00Z","modified":"2026-07-13T07:26:44.131167989Z","aliases":["CVE-2026-35536","GHSA-fqwm-6jpj-5wxc","PYSEC-2026-2287"],"related":["CGA-fhq4-732h-4f38"],"summary":"Tornado has incomplete validation of cookie attributes","details":"Values passed to the `domain`, `path`, and `samesite` arguments of `RequestHandler.set_cookie` were not completely validated in versions of Tornado prior to 6.5.5. In particular, semicolons would be allowed, which could be used to inject attacker-controlled values for other cookie attributes.","affected":[{"package":{"name":"tornado","ecosystem":"PyPI","purl":"pkg:pypi/tornado"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.5.5"}]}],"versions":["0.2","1.0","1.1","1.1.1","1.2","1.2.1","2.0","2.1","2.1.1","2.2","2.2.1","2.3","2.4","2.4.1","3.0","3.0.1","3.0.2","3.1","3.1.1","3.2","3.2.1","3.2.2","4.0","4.0.1","4.0.2","4.1","4.1b2","4.2","4.2.1","4.2b1","4.3","4.3b1","4.3b2","4.4","4.4.1","4.4.2","4.4.3","4.4b1","4.5","4.5.1","4.5.2","4.5.3","4.5b1","4.5b2","5.0","5.0.1","5.0.2","5.0a1","5.0b1","5.1","5.1.1","5.1b1","6.0","6.0.1","6.0.2","6.0.3","6.0.4","6.0a1","6.0b1","6.1","6.1b1","6.1b2","6.2","6.2b1","6.2b2","6.3","6.3.1","6.3.2","6.3.3","6.3b1","6.4","6.4.1","6.4.2","6.4b1","6.5","6.5.1","6.5.2","6.5.3","6.5.4","6.5b1"],"database_specific":{"last_known_affected_version_range":"<= 6.5.4","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-78cv-mqj4-43f7/GHSA-78cv-mqj4-43f7.json"}}],"references":[{"type":"WEB","url":"https://github.com/tornadoweb/tornado/security/advisories/GHSA-78cv-mqj4-43f7"},{"type":"WEB","url":"https://github.com/tornadoweb/tornado/commit/24a2d96ea115f663b223887deb0060f13974c104"},{"type":"PACKAGE","url":"https://github.com/tornadoweb/tornado"},{"type":"WEB","url":"https://github.com/tornadoweb/tornado/releases/tag/v6.5.5"}],"database_specific":{"cwe_ids":["CWE-74"],"github_reviewed":true,"github_reviewed_at":"2026-03-11T22:17:00Z","nvd_published_at":null,"severity":"MODERATE"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"}]}