{"id":"CVE-2026-27145","revision":"17c06350ce0340fcb6acdcd70420a1ec","records":[{"revision":"17c06350ce0340fcb6acdcd70420a1ec","observedAt":"2026-10-25T06:17:28.833+00:00","statement":{"source":"nvd","id":"CVE-2026-27145","aliases":[],"title":"(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries. This caused strings.Split(host, \".\") to execute repeatedly on the same input hostname. With a large DNS SAN l…","description":"(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries. This caused strings.Split(host, \".\") to execute repeatedly on the same input hostname. With a large DNS SAN list, verification costs scaled quadratically based on the number of SAN entries multiplied by the hostname's label count. Because x509.Verify validates hostnames before building the certificate chain, this overhead occurred even for untrusted certificates.","state":0,"publishedAt":"2026-06-02T23:16:35.57+00:00","modifiedAt":"2026-09-18T13:17:43.283+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · 134c704f-9b21-4f2e-91b3-4a467353bcc0 · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H","score":6.5,"severity":"MEDIUM"},{"system":"CVSS 3.1 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://go.dev/cl/783621","https://go.dev/issue/79694","https://groups.google.com/g/golang-announce/c/tKs3rmcBcKw","https://pkg.go.dev/vuln/GO-2026-5037","https://access.redhat.com/errata/RHSA-2026:23262","https://access.redhat.com/errata/RHSA-2026:23264","https://access.redhat.com/errata/RHSA-2026:29980","https://access.redhat.com/errata/RHSA-2026:29981","https://access.redhat.com/errata/RHSA-2026:33574","https://access.redhat.com/errata/RHSA-2026:34357","https://access.redhat.com/errata/RHSA-2026:34359","https://access.redhat.com/errata/RHSA-2026:35832","https://access.redhat.com/errata/RHSA-2026:36317","https://access.redhat.com/errata/RHSA-2026:36648","https://access.redhat.com/errata/RHSA-2026:36797","https://access.redhat.com/errata/RHSA-2026:38995","https://access.redhat.com/errata/RHSA-2026:39005","https://access.redhat.com/errata/RHSA-2026:39573","https://access.redhat.com/errata/RHSA-2026:39879","https://access.redhat.com/errata/RHSA-2026:41030","https://access.redhat.com/errata/RHSA-2026:41036","https://access.redhat.com/errata/RHSA-2026:41930","https://access.redhat.com/errata/RHSA-2026:42043","https://access.redhat.com/errata/RHSA-2026:42047","https://access.redhat.com/errata/RHSA-2026:42049","https://access.redhat.com/errata/RHSA-2026:42050","https://access.redhat.com/errata/RHSA-2026:42051","https://access.redhat.com/errata/RHSA-2026:42079","https://access.redhat.com/errata/RHSA-2026:42080","https://access.redhat.com/errata/RHSA-2026:42082","https://access.redhat.com/errata/RHSA-2026:42142","https://access.redhat.com/errata/RHSA-2026:42150","https://access.redhat.com/errata/RHSA-2026:42151","https://access.redhat.com/errata/RHSA-2026:42240","https://access.redhat.com/errata/RHSA-2026:42644","https://access.redhat.com/errata/RHSA-2026:42946","https://access.redhat.com/errata/RHSA-2026:44622","https://access.redhat.com/errata/RHSA-2026:46394","https://access.redhat.com/errata/RHSA-2026:46395","https://access.redhat.com/errata/RHSA-2026:47149","https://access.redhat.com/errata/RHSA-2026:47735","https://access.redhat.com/errata/RHSA-2026:47737","https://access.redhat.com/errata/RHSA-2026:49702","https://access.redhat.com/errata/RHSA-2026:49703","https://access.redhat.com/errata/RHSA-2026:49705","https://access.redhat.com/errata/RHSA-2026:49712","https://access.redhat.com/errata/RHSA-2026:49729","https://access.redhat.com/errata/RHSA-2026:49744","https://access.redhat.com/errata/RHSA-2026:49765","https://access.redhat.com/errata/RHSA-2026:49770","https://access.redhat.com/errata/RHSA-2026:50205","https://access.redhat.com/errata/RHSA-2026:50319","https://access.redhat.com/errata/RHSA-2026:51057","https://access.redhat.com/errata/RHSA-2026:51187","https://access.redhat.com/errata/RHSA-2026:52946","https://access.redhat.com/errata/RHSA-2026:53374","https://access.redhat.com/errata/RHSA-2026:53412","https://access.redhat.com/errata/RHSA-2026:53413","https://access.redhat.com/errata/RHSA-2026:53415","https://access.redhat.com/errata/RHSA-2026:53416","https://access.redhat.com/errata/RHSA-2026:53530","https://access.redhat.com/errata/RHSA-2026:54168","https://access.redhat.com/errata/RHSA-2026:54401","https://access.redhat.com/errata/RHSA-2026:54427","https://access.redhat.com/errata/RHSA-2026:54432","https://access.redhat.com/errata/RHSA-2026:54435","https://access.redhat.com/errata/RHSA-2026:54441","https://access.redhat.com/errata/RHSA-2026:54500","https://access.redhat.com/errata/RHSA-2026:54525","https://access.redhat.com/errata/RHSA-2026:54531","https://access.redhat.com/errata/RHSA-2026:54603","https://access.redhat.com/errata/RHSA-2026:54757","https://access.redhat.com/errata/RHSA-2026:55899","https://access.redhat.com/errata/RHSA-2026:57194","https://access.redhat.com/errata/RHSA-2026:57482","https://access.redhat.com/errata/RHSA-2026:57488","https://access.redhat.com/errata/RHSA-2026:57649","https://access.redhat.com/errata/RHSA-2026:59556","https://access.redhat.com/errata/RHSA-2026:59557","https://access.redhat.com/errata/RHSA-2026:59558","https://access.redhat.com/errata/RHSA-2026:59559","https://access.redhat.com/errata/RHSA-2026:59579","https://access.redhat.com/errata/RHSA-2026:59593","https://access.redhat.com/errata/RHSA-2026:60025","https://access.redhat.com/errata/RHSA-2026:60315","https://access.redhat.com/errata/RHSA-2026:60354","https://access.redhat.com/errata/RHSA-2026:60386","https://access.redhat.com/errata/RHSA-2026:60387","https://access.redhat.com/errata/RHSA-2026:60388","https://access.redhat.com/errata/RHSA-2026:60390","https://access.redhat.com/errata/RHSA-2026:60391","https://access.redhat.com/errata/RHSA-2026:61253","https://access.redhat.com/errata/RHSA-2026:61314","https://access.redhat.com/errata/RHSA-2026:63016","https://access.redhat.com/errata/RHSA-2026:66022","https://access.redhat.com/errata/RHSA-2026:68334","https://access.redhat.com/errata/RHSA-2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NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Awaiting Analysis","weaknesses":["CWE-606"],"productCriteria":[],"sourceDates":{"published":"2026-06-02T23:16:35.570","lastModified":"2026-09-18T13:17:43.283"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-27145","identifiers":["CVE-2026-27145"]},"retained":false,"historicalAffected":[]}],"coverage":[]}