{"affected":[{"defaultStatus":"unaffected","product":"CPython","source":"CNA: PSF","vendor":"Python Software Foundation","versions":[{"lessThan":"3.16.0","status":"affected","version":"0","versionType":"python"}]}],"cveId":"CVE-2026-16052","cwes":["CWE-74"],"description":"The http.cookies.Morsel class allows separator semicolons in attribute\nvalues\nand includes them verbatim in all output formats. An attacker who can\ncontrol\nthese values could use this to relax the cookie's Domain or SameSite\nrestrictions.","epss":null,"exploits":[],"kev":null,"metrics":[{"score":2.3,"severity":"low","source":"CNA: PSF","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"},{"score":2.3,"severity":"low","source":"NVD: cna@python.org","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/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"}],"modifiedAt":1794503864353,"publishedAt":1794500883251,"references":[{"source":"CNA: PSF","tags":[],"url":"https://github.com/python/cpython/pull/161711"},{"source":"CNA: PSF","tags":[],"url":"https://github.com/python/cpython/issues/161707"},{"source":"CNA: PSF","tags":[],"url":"https://mail.python.org/archives/list/security-announce@python.org/thread/IZL4QUFV7PKGT2JYSU2DCBMLTWYJDGKZ/"},{"source":"cna@python.org","tags":[],"url":"https://github.com/python/cpython/issues/161707"},{"source":"cna@python.org","tags":[],"url":"https://github.com/python/cpython/pull/161711"},{"source":"cna@python.org","tags":[],"url":"https://mail.python.org/archives/list/security-announce@python.org/thread/IZL4QUFV7PKGT2JYSU2DCBMLTWYJDGKZ/"}],"remediation":[],"revision":"b4f18d3b1ad53c9751f5e3c046b0f9e37c1c7e51e1d05b02d98b09dbad269ec2","sources":[{"modifiedAt":1794500883251,"name":"CNA: PSF","retrievedAt":1794503453680,"url":"https://www.cve.org/CVERecord?id=CVE-2026-16052"},{"modifiedAt":1794503864353,"name":"NVD","retrievedAt":1794507525235,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-16052"}],"ssvc":null,"status":"published","title":"Cookie Attribute Injection via Unescaped Semicolons in http.cookies.Morsel","updatedAt":1794507525235}