{"id":"CVE-2026-42505","summary":"Invoking Encrypted Client Hello privacy leak in crypto/tls","details":"Handshakes which used Encrypted Client Hello could be de-anonymized by a passive network observer due to a disclosure of pre-shared key identities in the unencrypted client hello.","aliases":["BIT-golang-2026-42505","GO-2026-5856"],"modified":"2026-09-18T03:46:32.196908199Z","published":"2026-07-08T15:46:33.407Z","related":["SUSE-SU-2026:22638-1","SUSE-SU-2026:22641-1","SUSE-SU-2026:22643-1","SUSE-SU-2026:22656-1","SUSE-SU-2026:2817-1","SUSE-SU-2026:2818-1","SUSE-SU-2026:3046-1","SUSE-SU-2026:3047-1","SUSE-SU-2026:3102-1","SUSE-SU-2026:3151-1","openSUSE-SU-2026:11212-1","openSUSE-SU-2026:11216-1","openSUSE-SU-2026:11232-1","openSUSE-SU-2026:11471-1","openSUSE-SU-2026:11798-1","openSUSE-SU-2026:21319-1","openSUSE-SU-2026:21321-1","openSUSE-SU-2026:21324-1","openSUSE-SU-2026:21341-1","openSUSE-SU-2026:21483-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42505.json","unresolved_ranges":[{"extracted_events":[{"fixed":"1.25.12"},{"introduced":"1.26.0-0"},{"fixed":"1.26.5"},{"introduced":"1.27.0-0"},{"fixed":"1.27.0-rc.2"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"Go"},"references":[{"type":"WEB","url":"https://go.dev/cl/775960"},{"type":"WEB","url":"https://go.dev/issue/79282"},{"type":"WEB","url":"https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc"},{"type":"WEB","url":"https://pkg.go.dev"},{"type":"WEB","url":"https://pkg.go.dev/vuln/GO-2026-5856"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42505.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42505"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/golang/go","events":[{"introduced":"6885bad7dd86880be6929c02085e5c7a67ff2887"},{"fixed":"d80d9a98f7e3a8f9b3a82d2c6079f84eb1101d46"},{"introduced":"d90b98e65320778f3b1f99a6951ab20f04d218b3"},{"fixed":"c19862e5f8415b4f24b189d065ed739517c548ba"},{"introduced":"eefb454307250192f45fa3718685e4c0a90e281d"},{"last_affected":"eefb454307250192f45fa3718685e4c0a90e281d"}],"database_specific":{"source":["CPE_RANGE","CPE_STRING"],"cpe":["cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*","cpe:2.3:a:golang:go:1.27:rc1:*:*:*:*:*:*"],"extracted_events":[{"introduced":"1.23.0"},{"fixed":"1.25.12"},{"introduced":"1.26.0"},{"fixed":"1.26.5"},{"introduced":"1.27-rc1"},{"last_affected":"1.27-rc1"}]}}],"versions":["1.27-rc1","go1.27rc1","go1.26.4","go1.26.3","go1.26.2","go1.26.1","go1.26.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-42505.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"}]}