{"id":"GHSA-px8h-6qxv-m22q","summary":"Incorrect parsing of nameless cookies leads to __Host- cookies bypass","details":"Browsers may allow \"nameless\" cookies that look like `=value` instead of `key=value`. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like `=__Host-test=bad` for another subdomain.\n\nWerkzeug \u003c= 2.2.2 will parse the cookie `=__Host-test=bad` as `__Host-test=bad`. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.","aliases":["CVE-2023-23934","PYSEC-2023-57"],"modified":"2026-09-10T03:50:07.890803222Z","published":"2023-02-15T15:37:03Z","database_specific":{"nvd_published_at":"2023-02-14T20:15:00Z","cwe_ids":["CWE-20"],"severity":"LOW","github_reviewed":true,"github_reviewed_at":"2023-02-15T15:37:03Z"},"references":[{"type":"WEB","url":"https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-23934"},{"type":"WEB","url":"https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028"},{"type":"PACKAGE","url":"https://github.com/pallets/werkzeug"},{"type":"WEB","url":"https://github.com/pallets/werkzeug/releases/tag/2.2.3"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/werkzeug/PYSEC-2023-57.yaml"},{"type":"WEB","url":"https://security.netapp.com/advisory/ntap-20230818-0003"},{"type":"WEB","url":"https://www.debian.org/security/2023/dsa-5470"}],"affected":[{"package":{"name":"werkzeug","ecosystem":"PyPI","purl":"pkg:pypi/werkzeug"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.3"}]}],"versions":["0.1","0.10","0.10.1","0.10.2","0.10.3","0.10.4","0.11","0.11.1","0.11.10","0.11.11","0.11.12","0.11.13","0.11.14","0.11.15","0.11.2","0.11.3","0.11.4","0.11.5","0.11.6","0.11.7","0.11.8","0.11.9","0.12","0.12.1","0.12.2","0.13","0.14","0.14.1","0.15.0","0.15.1","0.15.2","0.15.3","0.15.4","0.15.5","0.15.6","0.16.0","0.16.1","0.2","0.3","0.3.1","0.4","0.4.1","0.5","0.5.1","0.6","0.6.1","0.6.2","0.7","0.7.1","0.7.2","0.8","0.8.1","0.8.2","0.8.3","0.9","0.9.1","0.9.2","0.9.3","0.9.4","0.9.5","0.9.6","1.0.0","1.0.0rc1","1.0.1","2.0.0","2.0.0rc1","2.0.0rc2","2.0.0rc3","2.0.0rc4","2.0.0rc5","2.0.1","2.0.2","2.0.3","2.1.0","2.1.1","2.1.2","2.2.0","2.2.0a1","2.2.1","2.2.2"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/02/GHSA-px8h-6qxv-m22q/GHSA-px8h-6qxv-m22q.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N"}]}