{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-6276","assignerOrgId":"2499f714-1537-4658-8207-48ae4bb9eae9","state":"PUBLISHED","assignerShortName":"curl","dateReserved":"2026-04-14T14:01:54.772Z","datePublished":"2026-05-13T08:28:19.273Z","dateUpdated":"2026-09-15T06:03:04.059Z"},"containers":{"cna":{"providerMetadata":{"orgId":"2499f714-1537-4658-8207-48ae4bb9eae9","shortName":"curl","dateUpdated":"2026-09-15T06:03:04.059Z"},"title":"stale custom cookie host causes cookie leak","descriptions":[{"lang":"en","value":"Using libcurl, when a custom `Host:` header is first set for an HTTP request\nand a second request is subsequently done using the same *easy handle* but\nwithout the custom `Host:` header set, the second request would use stale\ninformation and pass on cookies meant for the first host in the second\nrequest. Leak them."}],"affected":[{"vendor":"curl","product":"curl","versions":[{"version":"7.71.0","status":"affected","versionType":"semver","lessThan":"8.14.2"},{"version":"8.15.0","status":"affected","versionType":"semver","lessThan":"8.16.1"},{"version":"8.17.0","status":"affected","versionType":"semver","lessThan":"8.20.0"}],"defaultStatus":"unaffected"},{"vendor":"curl","product":"curl","versions":[{"version":"e15e51384a423be31318b3c9c7d612a1aae661fd","status":"affected","versionType":"git","lessThan":"3a19987a87f393d9394fe5acc7643f6c263c92db"}],"defaultStatus":"unaffected","repo":"https://github.com/curl/curl.git"},{"vendor":"curl","product":"curl","versions":[{"version":"8.19.0","status":"affected"},{"version":"8.18.0","status":"affected"},{"version":"8.17.0","status":"affected"},{"version":"8.16.0","status":"affected"},{"version":"8.15.0","status":"affected"},{"version":"8.14.1","status":"affected"},{"version":"8.14.0","status":"affected"},{"version":"8.13.0","status":"affected"},{"version":"8.12.1","status":"affected"},{"version":"8.12.0","status":"affected"},{"version":"8.11.1","status":"affected"},{"version":"8.11.0","status":"affected"},{"version":"8.10.1","status":"affected"},{"version":"8.10.0","status":"affected"},{"version":"8.9.1","status":"affected"},{"version":"8.9.0","status":"affected"},{"version":"8.8.0","status":"affected"},{"version":"8.7.1","status":"affected"},{"version":"8.7.0","status":"affected"},{"version":"8.6.0","status":"affected"},{"version":"8.5.0","status":"affected"},{"version":"8.4.0","status":"affected"},{"version":"8.3.0","status":"affected"},{"version":"8.2.1","status":"affected"},{"version":"8.2.0","status":"affected"},{"version":"8.1.2","status":"affected"},{"version":"8.1.1","status":"affected"},{"version":"8.1.0","status":"affected"},{"version":"8.0.1","status":"affected"},{"version":"8.0.0","status":"affected"},{"version":"7.88.1","status":"affected"},{"version":"7.88.0","status":"affected"},{"version":"7.87.0","status":"affected"},{"version":"7.86.0","status":"affected"},{"version":"7.85.0","status":"affected"},{"version":"7.84.0","status":"affected"},{"version":"7.83.1","status":"affected"},{"version":"7.83.0","status":"affected"},{"version":"7.82.0","status":"affected"},{"version":"7.81.0","status":"affected"},{"version":"7.80.0","status":"affected"},{"version":"7.79.1","status":"affected"},{"version":"7.79.0","status":"affected"},{"version":"7.78.0","status":"affected"},{"version":"7.77.0","status":"affected"},{"version":"7.76.1","status":"affected"},{"version":"7.76.0","status":"affected"},{"version":"7.75.0","status":"affected"},{"version":"7.74.0","status":"affected"},{"version":"7.73.0","status":"affected"},{"version":"7.72.0","status":"affected"},{"version":"7.71.1","status":"affected"},{"version":"7.71.0","status":"affected"}],"defaultStatus":"unaffected"}],"references":[{"url":"https://curl.se/docs/CVE-2026-6276.json"},{"url":"https://curl.se/docs/CVE-2026-6276.html"},{"url":"https://hackerone.com/reports/3671818"}],"x_osv":{"schema_version":"1.5.0","id":"CURL-CVE-2026-6276","aliases":["CVE-2026-6276"],"summary":"stale custom cookie host causes cookie leak","modified":"2026-09-07T10:34:51.00Z","database_specific":{"package":"curl","affects":"lib","URL":"https://curl.se/docs/CVE-2026-6276.json","www":"https://curl.se/docs/CVE-2026-6276.html","issue":"https://hackerone.com/reports/3671818","CWE":{"id":"CWE-346","desc":"Origin Validation Error"},"last_affected":"8.19.0","severity":"Low"},"published":"2026-04-29T08:00:00.00Z","affected":[{"ranges":[{"type":"SEMVER","events":[{"introduced":"7.71.0"},{"fixed":"8.14.2"},{"introduced":"8.15.0"},{"fixed":"8.16.1"},{"introduced":"8.17.0"},{"fixed":"8.20.0"}]},{"type":"GIT","repo":"https://github.com/curl/curl.git","events":[{"introduced":"e15e51384a423be31318b3c9c7d612a1aae661fd"},{"fixed":"3a19987a87f393d9394fe5acc7643f6c263c92db"}]}],"versions":["8.19.0","8.18.0","8.17.0","8.16.0","8.15.0","8.14.1","8.14.0","8.13.0","8.12.1","8.12.0","8.11.1","8.11.0","8.10.1","8.10.0","8.9.1","8.9.0","8.8.0","8.7.1","8.7.0","8.6.0","8.5.0","8.4.0","8.3.0","8.2.1","8.2.0","8.1.2","8.1.1","8.1.0","8.0.1","8.0.0","7.88.1","7.88.0","7.87.0","7.86.0","7.85.0","7.84.0","7.83.1","7.83.0","7.82.0","7.81.0","7.80.0","7.79.1","7.79.0","7.78.0","7.77.0","7.76.1","7.76.0","7.75.0","7.74.0","7.73.0","7.72.0","7.71.1","7.71.0"]}],"credits":[{"name":"Muhamad Arga Reksapati","type":"finder"},{"name":"Daniel Stenberg","type":"remediation developer"}],"details":"Using libcurl, when a custom `Host:` header is first set for an HTTP request\nand a second request is subsequently done using the same *easy handle* but\nwithout the custom `Host:` header set, the second request would use stale\ninformation and pass on cookies meant for the first host in the second\nrequest. Leak them."},"problemTypes":[{"descriptions":[{"lang":"en","description":"Origin Validation Error","cweId":"CWE-346","type":"CWE"}]}],"credits":[{"lang":"en","value":"Muhamad Arga Reksapati","type":"finder"},{"lang":"en","value":"Daniel Stenberg","type":"remediation developer"}],"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2026/04/29/13"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2026-05-13T09:05:37.539Z"}},{"references":[{"url":"https://hackerone.com/reports/3671818","tags":["exploit"]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.5,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-05-13T17:24:29.094167Z","id":"CVE-2026-6276","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-13T17:26:06.894Z"}}]}}