{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-39821", "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc", "state": "PUBLISHED", "assignerShortName": "Go", "dateReserved": "2026-04-07T18:13:03.526Z", "datePublished": "2026-05-22T15:01:21.462Z", "dateUpdated": "2026-06-30T03:15:52.607Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc", "shortName": "Go", "dateUpdated": "2026-05-22T15:01:21.462Z"}, "title": "Invoking failure to reject ASCII-only Punycode-encoded labels in golang.org/x/net/idna", "descriptions": [{"lang": "en", "value": "The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode(\"xn--example-.com\") incorrectly returns the name \"example.com\" rather than an error. This behavior can lead to privilege escalation in programs using the idna package. 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{}

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