{"id":"CVE-2021-31921","aliases":["EUVD-2021-18794","GHSA-3j84-jghj-gqwg","RHSA-2021:2061","RHSA-2021:2085"],"status":"published","title":"Istio before 1.8.6 and 1.9.x before 1.9.5, when a gateway is using the AUTO_PASSTHROUGH routing...","description":"Istio before 1.8.6 and 1.9.x before 1.9.5 contains a remotely exploitable vulnerability where an external client can access unexpected services in the cluster, bypassing authorization checks, when a gateway is configured with AUTO_PASSTHROUGH routing configuration.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.01454,"percentile":0.73828,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-862"],"published":"2021-06-02T15:36:41Z","modified":"2026-10-24T10:30:17Z","fixes":[{"ecosystem":"Red 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