{"id":"CVE-2026-100724","revision":null,"records":[{"revision":"93fe6257b4b045048584071e1fec1a0c","observedAt":"2026-10-29T22:48:55.035+00:00","statement":{"source":"cve-program","id":"CVE-2026-100724","aliases":[],"title":"http4k before 6.49.0.0 Host Header Routing Bypass via reverseProxy","description":"http4k (Maven package org.http4k:http4k-core) before 6.49.0.0, 5.42.0.0 and 4.51.0.0 uses substring (Contains) matching on the Host header by default in reverseProxy() and reverseProxyRouting() when dispatching to configured virtual hosts. If these functions are deployed as a public-facing inbound HTTP handler with two or more configured virtual hosts, a remote attacker can supply a Host header that merely contains a configured vhost name (for example Host: admin.evil.com for a vhost configured as \"admin\") and be routed to that vhost, bypassing routing-based authorization. The intended outbound-dispatch and test-time uses, where the Host value is set by the calling application, are not affected.","state":0,"publishedAt":"2026-09-27T01:28:30.71+00:00","modifiedAt":"2026-10-29T21:15:26.111+00:00","affected":[{"ecosystem":"Vendor product","name":"http4k","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"http4k\",\n                    \"product\": \"http4k\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageURL\": \"pkg:maven/org.http4k/http4k-core\",\n                    \"versions\": [\n                        {\n                            \"version\": \"6.0.0.0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"custom\",\n                            \"lessThan\": \"6.49.0.0\"\n                        },\n                        {\n                            \"version\": \"6.49.0.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"custom\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"http4k","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"http4k\",\n                    \"product\": \"http4k\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageURL\": \"pkg:maven/org.http4k/http4k-core\",\n                    \"versions\": [\n                        {\n                            \"version\": \"5.0.0.0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"custom\",\n                            \"lessThan\": \"5.42.0.0\"\n                        },\n                        {\n                            \"version\": \"5.42.0.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"custom\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"http4k","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"http4k\",\n                    \"product\": \"http4k\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageURL\": \"pkg:maven/org.http4k/http4k-core\",\n                    \"versions\": [\n                        {\n                            \"version\": \"0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"custom\",\n                            \"lessThan\": \"4.51.0.0\"\n                        },\n                        {\n                            \"version\": \"4.51.0.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"custom\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","score":6.3,"severity":"MEDIUM"},{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","score":5.4,"severity":"MEDIUM"}],"references":["https://github.com/http4k/http4k/security/advisories/GHSA-jrpc-7vxp-69p6","https://github.com/http4k/http4k/commit/0121b05537","https://github.com/http4k/http4k/commit/54c6385615","https://www.vulncheck.com/advisories/http4k-before-6.49.0.0-host-header-routing-bypass-via-reverseproxy"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-100724","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-100724","identifiers":["CVE-2026-100724"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-07T01:26:54.7341767+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-07T01:26:54.7341767+00:00","lastSuccessAt":"2026-11-07T01:26:54.8876863+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:54.8876872+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-e3f76855f3f449c8c0427e4ebd06d00838fa519af10fe158fc0ca4a62af0718a-340a45d9017d4f9de046b855ad9d1afbc5c699f0e6a7003981ff3a54ebedd5b3","complete":true,"records":420470,"lastAttemptAt":"2026-11-07T01:26:54.2134599+00:00","lastSuccessAt":"2026-11-06T23:27:15.9170833+00:00","error":"InvalidOperationException","lastVerifiedAt":"2026-11-07T00:26:54.2874398+00:00","snapshotPublishedAt":"2026-11-06T23:24:11+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-1e21f19531e44b2e94a04caf6ae93614","complete":true,"records":13623,"lastAttemptAt":"2026-11-07T01:38:26.744654+00:00","lastSuccessAt":"2026-11-07T01:38:26.741+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:38:26.741+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13685,"expectedIdentifiers":13685,"failedIdentifiers":0},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-07T01:26:54.7341767+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-07T01:26:54.7341767+00:00","lastSuccessAt":"2026-11-07T01:26:54.8884513+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:54.8884516+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-34343b4ea57e47c5a482c8fcf20a381e","complete":true,"records":13645,"lastAttemptAt":"2026-11-07T01:26:55.9490879+00:00","lastSuccessAt":"2026-11-07T01:26:55.938+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:55.938+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13685,"expectedIdentifiers":13685,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-0eb4d6dde62dffacd040ad992d4fd5a65cd7d0dc5f5f4cfa8b41967fc6f9ca5f","complete":true,"records":9914,"lastAttemptAt":"2026-11-07T01:26:54.5768376+00:00","lastSuccessAt":"2026-11-06T20:10:36.6450506+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:54.5768376+00:00","snapshotPublishedAt":"2026-11-06T20:02:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-fde804134ecdda0ddd5ff5c26ee1fff5a6fa659311f7ef2e51c6ad54964db0e2","complete":true,"records":1971,"lastAttemptAt":"2026-11-07T01:26:54.3688172+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:54.3688172+00:00","snapshotPublishedAt":"2026-11-06T18:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-335633e78a15c9cde10a6025895b5617717087fb945489ae7e15d377bacf34a9","complete":true,"records":3055,"lastAttemptAt":"2026-11-07T01:26:54.6823337+00:00","lastSuccessAt":"2026-11-06T16:03:00.7615789+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:54.6823337+00:00","snapshotPublishedAt":"2026-11-06T16:02:48+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-a0b728bc1c5526b5429930c00621636eba8655069c176697c3080f8377619ad7","complete":true,"records":231291,"lastAttemptAt":"2026-11-07T01:26:54.4691469+00:00","lastSuccessAt":"2026-11-07T00:28:51.1983528+00:00","error":null,"lastVerifiedAt":"2026-11-07T01:26:54.4691469+00:00","snapshotPublishedAt":"2026-11-06T23:33:08+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}