{"schemaVersion":3,"id":"CVE-2020-11767","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Istio through 1.5.1 and Envoy through 1.14.1 have a data-leak issue. If there is a TCP connection (negotiated with SNI over HTTPS) to *.example.com, a request for a domain concurrently configured explicitly (e.g., abc.example.com) is sent to the server(s) listening behind *.example.com. The outcome should instead be 421 Misdirected Request. Imagine a shared caching forward proxy re-using an HTTP/2 connection for a large subnet with many users. If a victim is interacting with abc.example.com, and a server (for abc.example.com) recycles the TCP connection to the forward proxy, the victim's browser may suddenly start sending sensitive data to a *.example.com server. This occurs because the forward proxy between the victim and the origin server reuses connections (which obeys the specification), but neither Istio nor Envoy corrects this by sending a 421 error. Similarly, this behavior voids the security model browsers have put in place between domains.","dates":{"published":"2020-04-15T01:05:38.000Z","modified":"2024-08-04T11:41:59.750Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":3.1,"severity":"low","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":3.1,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":2.6,"severity":"low","vector":"AV:N/AC:H/Au:N/C:P/I:N/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.01818,"percentile":0.78412,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.01818},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01818,"percentile":0.78412}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01818,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01818,"percentile":null},{"d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