{"id":"CVE-2018-16886","aliases":["GHSA-h6xx-pmxh-3wgp","GO-2021-0077"],"url":"https://o3.security/vulnerability/CVE-2018-16886","summary":"go.etcd.io/etcd Authentication Bypass","details":"etcd versions 3.2.x before 3.2.26 and 3.3.x before 3.3.11 are vulnerable to an improper authentication issue when role-based access control (RBAC) is used and client-cert-auth is enabled. If an etcd client server TLS certificate contains a Common Name (CN) which matches a valid RBAC username, a remote attacker may authenticate as that user with any valid (trusted) client certificate in a REST API request to the gRPC-gateway.","published":"2019-01-14T19:29:00.243Z","modified":"2026-07-08T05:52:21.235972305Z","cvss":{"score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":{"score":0.04031,"percentile":0.90096,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"go.etcd.io/etcd/v3","fixedVersion":"3.2.26"},{"ecosystem":"Go","name":"go.etcd.io/etcd/v3","fixedVersion":"3.3.11"},{"ecosystem":"Go","name":"go.etcd.io/etcd","fixedVersion":"0.5.0-alpha.5.0.20190108173120-83c051b701d3"}],"fix":null,"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JX7QTIT465BQGRGNCE74RATRQLKT2QE4/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UPGYHMSKDPW5GAMI7BEP3XQRVRLLBJKS/"},{"type":"ADVISORY","url":"http://www.securityfocus.com/bid/106540"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2019:0237"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2019:1352"},{"type":"ADVISORY","url":"https://github.com/etcd-io/etcd/blob/1eee465a43720d713bb69f7b7f5e120135fdb1ac/CHANGELOG-3.2.md#security-authentication"},{"type":"ADVISORY","url":"https://github.com/etcd-io/etcd/blob/1eee465a43720d713bb69f7b7f5e120135fdb1ac/CHANGELOG-3.3.md#security-authentication"},{"type":"FIX","url":"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16886"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-08T05:52:21.235972305Z"}}