{"id":"CVE-2021-39242","details":"An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. It can lead to a situation with an attacker-controlled HTTP Host header, because a mismatch between Host and authority is mishandled.","aliases":["BIT-haproxy-2021-39242"],"modified":"2026-09-19T11:45:20.060305858Z","published":"2021-08-17T19:15:08.320Z","database_specific":{"unresolved_ranges":[{"source":"CPE_RANGE","vendor_product":"haproxy:haproxy","cpes":["cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.2.0"},{"fixed":"2.2.16"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"},{"introduced":"2.3.0"},{"fixed":"2.3.13"}]},{"cpes":["cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"11.0"},{"last_affected":"11.0"}],"source":"CPE_STRING","vendor_product":"debian:debian_linux"},{"source":"CPE_STRING","vendor_product":"fedoraproject:fedora","cpes":["cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*","cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"33"},{"last_affected":"33"},{"introduced":"34"},{"last_affected":"34"}]}]},"references":[{"type":"WEB","url":"https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=b5d2b9e154d78e4075db163826c5e0f6d31b2ab1"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/"},{"type":"WEB","url":"https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html"},{"type":"ADVISORY","url":"https://www.debian.org/security/2021/dsa-4960"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/haproxy/haproxy","events":[{"introduced":"6cbbecf09734aeb5fa8bb88f36f06a6f6d35e813"},{"fixed":"a786c41f1fa7abf85e76abfe1ba09b0aed99190d"}],"database_specific":{"extracted_events":[{"introduced":"2.4.0"},{"fixed":"2.4.3"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-39242.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}