{"id":"CVE-2026-73499","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-73499","summary":"etcd: Watch API authorization bypass via open-ended range requests","details":"### Impact\n_What kind of vulnerability is it? Who is impacted?_\n\nA user granted READ permission on a single, exact key can use the Watch gRPC API with `clientv3.WithFromKey()` (an open-ended, \"from this key to the end of the keyspace\" watch) to receive watch events for every key lexicographically greater than or equal to their permitted key — not just the one key they were granted. \n\nThis is an authorization bypass in etcd's RBAC enforcement for the Watch API; Range/Get and DeleteRange requests are not affected. It only affects clusters with authentication enabled — clusters running without auth already allow unrestricted read access.\n\n### Patches\n_Has the problem been patched? What versions should users upgrade to?_\n\nThis vulnerability is patched in the following versions:\n\n- etcd 3.7.1\n- etcd 3.6.14\n- etcd 3.5.33\n\n### Workarounds\n_Is there a way for users to fix or remediate the vulnerability without upgrading?_\n\nIf upgrading is not immediately possible, the following mitigations reduce exposure:\n\n- Audit READ grants. Any READ grant — even on one key — can be leveraged via Watch to read everything after it. Review who holds READ permissions and revoke/tighten any you wouldn't trust with full read access.\n- Restrict network access. Limit which hosts can reach etcd's client (gRPC) port via firewall rules or network policy, reducing who can attempt exploitation.\n\n### Reporter\n\n- Luis Toro ([@lobuhi](https://github.com/lobuhi) on Github)\n- Anthropic  and Adam Korczynski ([@AdamKorcz](https://github.com/AdamKorcz) on Github)","published":"2026-07-24T22:38:22Z","modified":"2026-08-12T21:30:07.601520195Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Go","name":"go.etcd.io/etcd/v3","fixedVersion":"3.7.1"},{"ecosystem":"Go","name":"go.etcd.io/etcd/v3","fixedVersion":"3.6.14"},{"ecosystem":"Go","name":"go.etcd.io/etcd/v3","fixedVersion":"3.5.33"}],"fix":{"url":"https://github.com/etcd-io/etcd/commit/6643f80602461a6095c9b294b6512fd9719bef41","label":"etcd-io/etcd@6643f80"},"references":[{"type":"WEB","url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-xg4h-6gfc-h4m8"},{"type":"WEB","url":"https://github.com/etcd-io/etcd/commit/6643f80602461a6095c9b294b6512fd9719bef41"},{"type":"WEB","url":"https://github.com/etcd-io/etcd/commit/afeaa624da19085b47fb5ccc7c22a8c421bc2eae"},{"type":"WEB","url":"https://github.com/etcd-io/etcd/commit/e863b001bbf3367003a543aa3099db9892134cd7"},{"type":"PACKAGE","url":"https://github.com/etcd-io/etcd"},{"type":"WEB","url":"https://github.com/etcd-io/etcd/releases/tag/v3.5.33"},{"type":"WEB","url":"https://github.com/etcd-io/etcd/releases/tag/v3.6.14"},{"type":"WEB","url":"https://github.com/etcd-io/etcd/releases/tag/v3.7.1"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T21:30:07.601520195Z"}}