{"id":"CVE-2020-11767","state":"PUBLISHED","title":"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 concurre","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.","publishedAt":"2020-04-15T01:05:38.000Z","updatedAt":"2024-08-04T11:41:59.750Z","severity":null,"assigner":"mitre","products":["n/a n/a"],"affected":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}],"references":["https://bugs.chromium.org/p/chromium/issues/detail?id=954160#c5","https://github.com/envoyproxy/envoy/issues/6767","https://github.com/istio/istio/issues/9429","https://github.com/istio/istio/issues/13589"],"weaknesses":[],"ingestedAt":"2026-10-29T19:46:24.834Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2020/11xxx/CVE-2020-11767.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2020-11767","state":"PUBLISHED","datePublished":"2020-04-15T01:05:38.000Z","dateUpdated":"2024-08-04T11:41:59.750Z","assignerShortName":"mitre","assignerOrgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","dateReserved":"2020-04-15T00:00:00.000Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}],"references":[{"url":"https://bugs.chromium.org/p/chromium/issues/detail?id=954160#c5","tags":["x_refsource_MISC"]},{"url":"https://github.com/envoyproxy/envoy/issues/6767","tags":["x_refsource_MISC"]},{"url":"https://github.com/istio/istio/issues/9429","tags":["x_refsource_MISC"]},{"url":"https://github.com/istio/istio/issues/13589","tags":["x_refsource_MISC"]}],"problemTypes":[{"descriptions":[{"description":"n/a","lang":"en","type":"text"}]}],"providerMetadata":{"shortName":"mitre","dateUpdated":"2020-04-15T01:05:38.000Z","orgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca"},"x_legacyV4Record":{"CVE_data_meta":{"ASSIGNER":"cve@mitre.org","ID":"CVE-2020-11767","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"n/a","version":{"version_data":[{"version_value":"n/a"}]}}]},"vendor_name":"n/a"}]}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"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."}]},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"n/a"}]}]},"references":{"reference_data":[{"name":"https://bugs.chromium.org/p/chromium/issues/detail?id=954160#c5","refsource":"MISC","url":"https://bugs.chromium.org/p/chromium/issues/detail?id=954160#c5"},{"name":"https://github.com/envoyproxy/envoy/issues/6767","refsource":"MISC","url":"https://github.com/envoyproxy/envoy/issues/6767"},{"name":"https://github.com/istio/istio/issues/9429","refsource":"MISC","url":"https://github.com/istio/istio/issues/9429"},{"name":"https://github.com/istio/istio/issues/13589","refsource":"MISC","url":"https://github.com/istio/istio/issues/13589"}]}}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://bugs.chromium.org/p/chromium/issues/detail?id=954160#c5","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://github.com/envoyproxy/envoy/issues/6767","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://github.com/istio/istio/issues/9429","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://github.com/istio/istio/issues/13589","tags":["x_refsource_MISC","x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-04T11:41:59.750Z"}}]}}}