{"id":"CVE-2019-18802","details":"An issue was discovered in Envoy 1.12.0. An untrusted remote client may send an HTTP header (such as Host) with whitespace after the header content. Envoy will treat \"header-value \" as a different string from \"header-value\" so for example with the Host header \"example.com \" one could bypass \"example.com\" matchers.","aliases":["GHSA-356m-vhw2-wcm4"],"modified":"2026-05-18T15:11:32.226104Z","published":"2019-12-13T13:15:11.383Z","related":["SUSE-SU-2020:0722-1","openSUSE-SU-2020:0379-1","openSUSE-SU-2021:0341-1","openSUSE-SU-2024:14491-1"],"references":[{"type":"WEB","url":"http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00034.html"},{"type":"WEB","url":"https://groups.google.com/forum/#%21forum/envoy-users"},{"type":"FIX","url":"https://github.com/envoyproxy/envoy/commits/master"},{"type":"ARTICLE","url":"https://blog.envoyproxy.io"},{"type":"EVIDENCE","url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-356m-vhw2-wcm4"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/envoyproxy/envoy","events":[{"introduced":"0"},{"last_affected":"44f8c365a1f1798f0af776f6aa64279dc68f5666"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"1.12.1"}],"source":"CPE_FIELD","cpe":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*"}}],"versions":["v1.12.1","v1.12.0","v1.11.0","v1.10.0","v1.9.0","v1.8.0","v1.7.0","v1.6.0","v1.5.0","v1.4.0","v1.3.0","v1.2.0","v1.1.0","v1.0.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2019-18802.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"}]}