{"id":"CVE-2023-23934","state":"PUBLISHED","title":"Wrkzeug's incorrect parsing of nameless cookies leads to __Host- cookies bypass","description":"Werkzeug is a comprehensive WSGI web application library. 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. Werkzeug prior to 2.2.3 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. The issue is fixed in Werkzeug 2.2.3.","publishedAt":"2023-02-14T19:56:22.659Z","updatedAt":"2025-03-10T21:11:36.910Z","severity":{"score":2.6,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["pallets werkzeug"],"affected":[{"vendor":"pallets","product":"werkzeug","versions":[{"version":"< 2.2.3","status":"affected"}]}],"references":["https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q","https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028","https://github.com/pallets/werkzeug/releases/tag/2.2.3","https://www.debian.org/security/2023/dsa-5470","https://security.netapp.com/advisory/ntap-20230818-0003/"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:05:43.909Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/23xxx/CVE-2023-23934.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2023-23934","state":"PUBLISHED","datePublished":"2023-02-14T19:56:22.659Z","dateUpdated":"2025-03-10T21:11:36.910Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2023-01-19T21:12:31.360Z"},"containers":{"cna":{"title":"Wrkzeug's incorrect parsing of nameless cookies leads to __Host- cookies bypass","descriptions":[{"lang":"en","value":"Werkzeug is a comprehensive WSGI web application library. 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. Werkzeug prior to 2.2.3 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. The issue is fixed in Werkzeug 2.2.3."}],"affected":[{"vendor":"pallets","product":"werkzeug","versions":[{"version":"< 2.2.3","status":"affected"}]}],"references":[{"url":"https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q","name":"https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028","name":"https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028","tags":["x_refsource_MISC"]},{"url":"https://github.com/pallets/werkzeug/releases/tag/2.2.3","name":"https://github.com/pallets/werkzeug/releases/tag/2.2.3","tags":["x_refsource_MISC"]},{"url":"https://www.debian.org/security/2023/dsa-5470"},{"url":"https://security.netapp.com/advisory/ntap-20230818-0003/"}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"ADJACENT_NETWORK","availabilityImpact":"NONE","baseScore":2.6,"baseSeverity":"LOW","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","description":"CWE-20: Improper Input Validation","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2023-08-18T13:06:20.023Z"},"source":{"advisory":"GHSA-px8h-6qxv-m22q","discovery":"UNKNOWN"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q","name":"https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q","tags":["x_refsource_CONFIRM","x_transferred"]},{"url":"https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028","name":"https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://github.com/pallets/werkzeug/releases/tag/2.2.3","name":"https://github.com/pallets/werkzeug/releases/tag/2.2.3","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://www.debian.org/security/2023/dsa-5470","tags":["x_transferred"]},{"url":"https://security.netapp.com/advisory/ntap-20230818-0003/","tags":["x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-02T10:49:07.628Z"}},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2025-03-10T20:57:36.294064Z","id":"CVE-2023-23934","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-03-10T21:11:36.910Z"}}]}}}