{"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": "2026-05-13T17:26:06.894Z"}, "containers": {"cna": {"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."}], "providerMetadata": {"orgId": "2499f714-1537-4658-8207-48ae4bb9eae9", "shortName": "curl", "dateUpdated": "2026-05-13T08:28:19.273Z"}, "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-346 Origin Validation Error"}]}], "affected": [{"vendor": "curl", "product": "curl", "versions": [{"version": "8.19.0", "status": "affected", "lessThanOrEqual": "8.19.0", "versionType": "semver"}, {"version": "8.18.0", "status": "affected", "lessThanOrEqual": "8.18.0", "versionType": "semver"}, {"version": "8.17.0", "status": "affected", "lessThanOrEqual": "8.17.0", "versionType": "semver"}, {"version": "8.16.0", "status": "affected", "lessThanOrEqual": "8.16.0", "versionType": "semver"}, {"version": "8.15.0", "status": "affected", "lessThanOrEqual": "8.15.0", "versionType": "semver"}, {"version": "8.14.1", "status": "affected", "lessThanOrEqual": "8.14.1", "versionType": "semver"}, {"version": "8.14.0", "status": "affected", "lessThanOrEqual": "8.14.0", "versionType": "semver"}, {"version": "8.13.0", "status": "affected", "lessThanOrEqual": "8.13.0", "versionType": "semver"}, {"version": "8.12.1", "status": "affected", "lessThanOrEqual": "8.12.1", "versionType": "semver"}, {"version": "8.12.0", "status": "affected", "lessThanOrEqual": "8.12.0", "versionType": "semver"}, {"version": "8.11.1", "status": "affected", "lessThanOrEqual": "8.11.1", "versionType": "semver"}, {"version": "8.11.0", "status": "affected", "lessThanOrEqual": "8.11.0", "versionType": "semver"}, {"version": "8.10.1", "status": "affected", "lessThanOrEqual": "8.10.1", "versionType": "semver"}, {"version": "8.10.0", "status": "affected", "lessThanOrEqual": "8.10.0", "versionType": "semver"}, {"version": "8.9.1", "status": "affected", "lessThanOrEqual": "8.9.1", "versionType": "semver"}, {"version": "8.9.0", "status": "affected", "lessThanOrEqual": "8.9.0", "versionType": "semver"}, {"version": "8.8.0", "status": "affected", "lessThanOrEqual": "8.8.0", "versionType": "semver"}, {"version": "8.7.1", "status": "affected", "lessThanOrEqual": "8.7.1", "versionType": "semver"}, {"version": "8.7.0", "status": "affected", "lessThanOrEqual": "8.7.0", "versionType": "semver"}, {"version": "8.6.0", "status": "affected", "lessThanOrEqual": "8.6.0", "versionType": "semver"}, {"version": "8.5.0", "status": "affected", "lessThanOrEqual": "8.5.0", "versionType": "semver"}, {"version": "8.4.0", "status": "affected", "lessThanOrEqual": "8.4.0", "versionType": "semver"}, {"version": "8.3.0", "status": "affected", "lessThanOrEqual": "8.3.0", "versionType": "semver"}, {"version": "8.2.1", "status": "affected", "lessThanOrEqual": "8.2.1", "versionType": "semver"}, {"version": "8.2.0", "status": "affected", "lessThanOrEqual": "8.2.0", "versionType": "semver"}, {"version": "8.1.2", "status": "affected", "lessThanOrEqual": "8.1.2", "versionType": "semver"}, {"version": "8.1.1", "status": "affected", "lessThanOrEqual": "8.1.1", "versionType": "semver"}, {"version": "8.1.0", "status": "affected", "lessThanOrEqual": "8.1.0", "versionType": "semver"}, {"version": "8.0.1", "status": "affected", "lessThanOrEqual": "8.0.1", "versionType": "semver"}, {"version": "8.0.0", "status": "affected", "lessThanOrEqual": "8.0.0", "versionType": "semver"}, {"version": "7.88.1", "status": "affected", "lessThanOrEqual": "7.88.1", "versionType": "semver"}, {"version": "7.88.0", "status": "affected", "lessThanOrEqual": "7.88.0", "versionType": "semver"}, {"version": "7.87.0", "status": "affected", "lessThanOrEqual": "7.87.0", "versionType": "semver"}, {"version": "7.86.0", "status": "affected", "lessThanOrEqual": "7.86.0", "versionType": "semver"}, {"version": "7.85.0", "status": "affected", "lessThanOrEqual": "7.85.0", "versionType": "semver"}, {"version": "7.84.0", "status": "affected", "lessThanOrEqual": "7.84.0", "versionType": "semver"}, {"version": "7.83.1", "status": "affected", "lessThanOrEqual": "7.83.1", "versionType": "semver"}, {"version": "7.83.0", "status": "affected", 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"lessThanOrEqual": "7.75.0", "versionType": "semver"}, {"version": "7.74.0", "status": "affected", "lessThanOrEqual": "7.74.0", "versionType": "semver"}, {"version": "7.73.0", "status": "affected", "lessThanOrEqual": "7.73.0", "versionType": "semver"}, {"version": "7.72.0", "status": "affected", "lessThanOrEqual": "7.72.0", "versionType": "semver"}, {"version": "7.71.1", "status": "affected", "lessThanOrEqual": "7.71.1", "versionType": "semver"}, {"version": "7.71.0", "status": "affected", "lessThanOrEqual": "7.71.0", "versionType": "semver"}], "defaultStatus": "unaffected"}], "references": [{"url": "https://curl.se/docs/CVE-2026-6276.json", "name": "json"}, {"url": "https://curl.se/docs/CVE-2026-6276.html", "name": "www"}, {"url": "https://hackerone.com/reports/3671818", "name": "issue"}], "credits": [{"lang": "en", "value": "Muhamad Arga Reksapati", "type": "finder"}, {"lang": "en", "value": "Daniel Stenberg", "type": "remediation developer"}]}, "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"}}]}}