{"affected":[{"defaultStatus":"unaffected","ecosystem":"pypi","packageName":"tornado","product":"tornado","source":"CNA: VulnCheck","vendor":"tornadoweb","versions":[{"lessThan":"6.6","status":"affected","version":"0","versionType":"custom"},{"status":"unaffected","version":"6.6","versionType":"custom"}]}],"cveId":"CVE-2026-123535","cwes":["CWE-74"],"description":"Tornado before 6.6 does not validate the max_age argument of RequestHandler.set_cookie (also called by set_signed_cookie, set_secure_cookie, and clear_cookie), allowing injection of additional Set-Cookie attributes. When an application passes attacker-influenced input as max_age, an attacker can embed attributes such as Domain, Path, or Secure to widen the cookie's scope to parent paths or other subdomains.","epss":{"date":"2026-11-12","percentile":0.06948,"score":0.00174},"exploits":[],"kev":null,"metrics":[{"score":2.3,"severity":"low","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"},{"score":4.2,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","version":"3.1"},{"score":2.3,"severity":"low","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","version":"4.0"},{"score":4.2,"severity":"medium","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","version":"3.1"}],"modifiedAt":1794492417116,"publishedAt":1794101863142,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/tornadoweb/tornado/security/advisories/GHSA-c6v4-qj2h-f748"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/tornado-before-6.6-cookie-attribute-injection-via-set-cookie-max-age"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/tornadoweb/tornado/security/advisories/GHSA-c6v4-qj2h-f748"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/tornado-before-6.6-cookie-attribute-injection-via-set-cookie-max-age"}],"remediation":[],"revision":"00421d0533fba5574e6fcd4bd77ff31c1a23fb1f0d6bbe7cca1c8be0e73fe6a0","sources":[{"modifiedAt":1794492417116,"name":"CNA: VulnCheck","retrievedAt":1794496267840,"url":"https://www.cve.org/CVERecord?id=CVE-2026-123535"},{"modifiedAt":1794104204053,"name":"NVD","retrievedAt":1794118570538,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-123535"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794496292230,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-123535"}],"ssvc":{"assessedAt":1794492406387,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Tornado before 6.6 Cookie Attribute Injection via set_cookie max_age","updatedAt":1794496292230}