{"id":"CVE-2026-123535","aliases":["AZL-113107","DEBIAN-CVE-2026-123535","EUVD-2026-119420","GHSA-c6v4-qj2h-f748","GHSA-cfc4-jgx9-vvjh","UBUNTU-CVE-2026-123535"],"status":"published","title":"Tornado before 6.6 Cookie Attribute Injection via set_cookie max_age","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.","severity":{"version":"4.0","score":2.3,"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","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00174,"percentile":0.06948,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-74"],"published":"2026-11-08T01:37:43Z","modified":"2026-11-12T17:25:21Z","affected":[{"source":"osv","ecosystem":"Azure Linux:3","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.3.3-11"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.2.0-3","6.2.0-3+deb12u1","6.2.0-3+deb12u2","6.2.0-3+deb12u3","6.2.0-3+deb12u4","6.3.2-1","6.4.0-1","6.4.0-2","6.4.1-1","6.4.1-2","6.4.1-3","6.4.2-1","6.4.2-2","6.4.2-3","6.5.2-1","6.5.2-2","6.5.2-3","6.5.4-0.1","6.5.4-1","6.5.5-1","6.5.5-2","6.5.5-3","6.5.5-4","6.5.5-5","6.6.0-1"]},{"source":"osv","ecosystem":"Debian:13","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.4.2-3","6.4.2-3+deb13u1","6.4.2-3+deb13u2","6.5.2-1","6.5.2-2","6.5.2-3","6.5.4-0.1","6.5.4-1","6.5.5-1","6.5.5-2","6.5.5-3","6.5.5-4","6.5.5-5","6.6.0-1"]},{"source":"osv","ecosystem":"Debian:14","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.4.2-3","6.5.2-1","6.5.2-2","6.5.2-3","6.5.4-0.1","6.5.4-1","6.5.5-1","6.5.5-2","6.5.5-3","6.5.5-4","6.5.5-5","6.6.0-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.1-1ubuntu2","4.2.1-1ubuntu3","4.2.1-1ubuntu3.1","4.2.1-1ubuntu3.1+esm1","4.2.1-1ubuntu3.1+esm2","4.2.1-1ubuntu3.1+esm3","4.2.1-1ubuntu3.1+esm4","4.2.1-1ubuntu3.1+esm5","4.2.1-1ubuntu3.1+esm6"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.5.1-2.1~build2","4.5.2-1","4.5.3-1","4.5.3-1ubuntu0.1","4.5.3-1ubuntu0.2","4.5.3-1ubuntu0.2+esm1","4.5.3-1ubuntu0.2+esm2","4.5.3-1ubuntu0.2+esm3","4.5.3-1ubuntu0.2+esm4","4.5.3-1ubuntu0.2+esm5","4.5.3-1ubuntu0.2+esm6"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.1.1-4ubuntu1","5.1.1-4ubuntu5","6.0.3+really5.1.1-2","6.0.3+really5.1.1-2build1","6.0.3+really5.1.1-2build2","6.0.3+really5.1.1-3","6.0.3+really5.1.1-3ubuntu0.1~esm1","6.0.3+really5.1.1-3ubuntu0.1~esm3","6.0.3+really5.1.1-3ubuntu0.1~esm5","6.0.3+really5.1.1-3ubuntu0.1~esm7","6.0.3+really5.1.1-3ubuntu0.1~esm8","6.0.3+really5.1.1-3ubuntu0.1~esm9"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.1.0-1build1","6.1.0-2","6.1.0-3","6.1.0-3build1","6.1.0-3ubuntu0.1~esm1","6.1.0-3ubuntu0.1~esm2","6.1.0-3ubuntu0.1~esm4","6.1.0-3ubuntu0.1~esm5","6.1.0-3ubuntu0.1~esm6","6.1.0-3ubuntu0.1~esm7","6.1.0-3ubuntu0.1~esm8"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.3.2-1","6.4.0-0ubuntu1","6.4.0-1","6.4.0-1build1","6.4.0-1ubuntu0.1","6.4.0-1ubuntu0.2","6.4.0-1ubuntu0.4","6.4.0-1ubuntu0.5","6.4.0-1ubuntu0.6","6.4.0-1ubuntu0.7","6.4.0-1ubuntu0.8"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.5.4-0.1","6.5.5-2","6.5.5-4","6.5.5-5","6.5.5-5ubuntu1.1","6.5.5-5ubuntu1.2","6.5.5-5ubuntu1.3"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"python-tornado","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.4.2-3","6.5.2-3","6.5.4-0.1","6.5.4-0.1ubuntu0.1","6.5.4-0.1ubuntu0.2","6.5.4-0.1ubuntu0.3","6.5.4-0.1ubuntu0.4"]}],"products":[{"vendor":"tornadoweb","product":"tornado"}],"references":[{"url":"https://github.com/tornadoweb/tornado/security/advisories/GHSA-c6v4-qj2h-f748","tags":["vendor-advisory","advisory","report"]},{"url":"https://www.vulncheck.com/advisories/tornado-before-6.6-cookie-attribute-injection-via-set-cookie-max-age","tags":["third-party-advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-123535","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-cfc4-jgx9-vvjh"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/123xxx/CVE-2026-123535.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-123535","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-123535","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-123535","tags":["report"]},{"url":"https://github.com/tornadoweb/tornado/pull/3763","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-123535","title":"Tornado before 6.6 Cookie Attribute Injection via set_cookie max_age","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.","status":"published","published":"2026-11-08T01:37:43.142Z","modified":"2026-11-12T14:06:57.116Z","cvss":[{"version":"4.0","score":2.3,"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","level":"low","assessor":"cna"},{"version":"3.1","score":4.2,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-74"],"updated_at":"2026-11-08T02:36:49.037074Z"}],"euvd":[{"id":"EUVD-2026-119420","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.","status":"published","published":"2026-11-08T01:37:43Z","modified":"2026-11-12T14:06:57Z","cvss":[{"version":"4.0","score":2.3,"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","level":"low"}],"updated_at":"2026-11-08T06:12:04.782489Z"}],"ghsa":[{"id":"GHSA-cfc4-jgx9-vvjh","title":"Tornado before 6.6 does not validate the max_age argument of RequestHandler.set_cookie (also...","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.","status":"published","published":"2026-11-08T03:30:31Z","modified":"2026-11-08T03:30:39Z","cvss":[{"version":"4.0","score":2.3,"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","level":"low"},{"version":"3.1","score":4.2,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-74"],"updated_at":"2026-11-08T03:41:53.166172Z"}],"nvd":[{"id":"CVE-2026-123535","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.","status":"published","published":"2026-11-08T02:16:43.917Z","modified":"2026-11-12T14:17:25.313Z","cvss":[{"version":"4.0","score":2.3,"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","level":"low","assessor":"secondary"},{"version":"3.1","score":4.2,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-74"],"updated_at":"2026-11-12T15:31:32.275584Z"}],"osv":[{"id":"CVE-2026-123535","title":"Tornado before 6.6 Cookie Attribute Injection via set_cookie max_age","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.","status":"published","published":"2026-11-08T01:37:43.142Z","modified":"2026-11-09T02:47:08.555857713Z","cvss":[{"version":"4.0","score":2.3,"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","level":"low"}],"cwes":["CWE-74"],"updated_at":"2026-11-08T11:04:05.022583Z"},{"id":"DEBIAN-CVE-2026-123535","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.","status":"published","published":"2026-11-08T02:16:43.917Z","modified":"2026-11-08T14:00:06.601199039Z","cvss":[{"version":"3.1","score":4.2,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-08T14:05:41.79473Z"},{"id":"UBUNTU-CVE-2026-123535","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.","status":"published","published":"2026-11-09T00:00:00Z","modified":"2026-11-12T17:25:21.513950751Z","cvss":[{"version":"3.1","score":4.2,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","level":"medium"},{"version":"4.0","score":2.3,"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","level":"low"}],"updated_at":"2026-11-12T18:05:20.870791Z"},{"id":"AZL-113107","title":"CVE-2026-123535 affecting package python-tornado 6.3.3-11","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.","status":"published","published":"2026-11-08T02:16:43Z","modified":"2026-11-11T14:17:32.123253508Z","updated_at":"2026-11-11T14:42:54.020399Z"}]}}