{"id":"CVE-2021-31921","details":"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.","modified":"2026-07-09T01:30:52.483436Z","published":"2021-06-02T16:15:08.927Z","references":[{"type":"EVIDENCE","url":"https://istio.io/latest/news/security/istio-security-2021-006/"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/istio/istio","events":[{"introduced":"0"},{"fixed":"1aa9fc7a594d6ffc88ff8fd6cd416d8bafe4b214"},{"introduced":"b63e1966c245924b10a0915a671a656540ed7a45"},{"fixed":"67362755b7ca63ff1442d627a733627ed5c75df4"}],"database_specific":{"cpe":"cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"1.8.6"},{"introduced":"1.9.0"},{"fixed":"1.9.5"}],"source":"CPE_RANGE"}}],"versions":["1.9.4","1.9.2","1.8.4","1.9.1","1.8.3","1.9.0","1.8.2","1.8.1","1.8.0-rc.1","1.8.0","1.8.0-rc.0","1.8.0-alpha.2","1.8.0-alpha.0","1.7.0-alpha.0","1.6.0-alpha.2","1.6.0-alpha.1","1.6.0-alpha.0","1.5.0-beta.2","1.5.0-beta.1","1.5.0-alpha.0","1.2.0-rc.3","1.2.0-rc.0","1.1.0-snapshot.2","1.1.0.snapshot.1","1.1.0.snapshot.0","1.0.0-snapshot.0","0.6.0","0.5.0","0.3.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-31921.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}