{"cve":"CVE-2026-6276","nvd":{"published":"2026-05-13T13:01:56.800","modified":"2026-09-15T07:16:29.343","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-319","CWE-346"],"references":["https://curl.se/docs/CVE-2026-6276.html","https://curl.se/docs/CVE-2026-6276.json","https://hackerone.com/reports/3671818","http://www.openwall.com/lists/oss-security/2026/04/29/13","https://hackerone.com/reports/3671818"],"products":["haxx:curl"],"source":"nvd","synced_at":"2026-10-19T22:35:16.954578616+00:00"},"epss":{"cve":"CVE-2026-6276","score":0.00295,"percentile":0.22158,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}