{"id":"CVE-2026-42273","summary":"Heimdall: Case-sensitive host matching may lead to policy bypass","details":"Heimdall is a cloud native Identity Aware Proxy and Access Control Decision service. Prior to version 0.17.14, Heimdall performs host matching in a case-sensitive manner, while HTTP hostnames are case-insensitive. This discrepancy can result in heimdall failing to match a rule for a request host that differs only in letter casing, potentially causing the request to be classified differently than intended. This issue has been patched in version 0.17.14.","aliases":["GHSA-72h4-mxfc-jx37","GO-2026-5200"],"modified":"2026-08-07T11:50:18.523301651Z","published":"2026-05-08T03:42:50.312Z","related":["openSUSE-SU-2026:21483-1"],"database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-178","CWE-436"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42273.json"},"references":[{"type":"WEB","url":"https://github.com/dadrus/heimdall/releases/tag/v0.17.14"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42273.json"},{"type":"ADVISORY","url":"https://github.com/dadrus/heimdall/security/advisories/GHSA-72h4-mxfc-jx37"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42273"},{"type":"FIX","url":"https://github.com/dadrus/heimdall/commit/3d05e56a9e7ef0355f17482b4322054af4e85943"},{"type":"FIX","url":"https://github.com/dadrus/heimdall/pull/3208"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/dadrus/heimdall","events":[{"introduced":"0"},{"fixed":"3d05e56a9e7ef0355f17482b4322054af4e85943"},{"fixed":"c89e65c0d7cc0c2456c067836614ab9190771088"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"0.17.14"}]}}],"versions":["v0.17.13","v0.17.12","v0.17.11","v0.17.10","v0.17.9","v0.17.8","v0.17.7","v0.17.6","v0.17.5","v0.17.4","v0.17.3","v0.17.2","v0.17.1","v0.17.0","v0.16.0","v0.15.0","v0.14.0-alpha","v0.13.0-alpha","v0.12.0-alpha","v0.11.1-alpha","v0.11.0-alpha","v0.10.1-alpha","v0.10.0-alpha","v0.9.1-alpha","v0.9.0-alpha","v0.8.2-alpha","v0.8.1-alpha","v0.8.0-alpha","v0.7.0-alpha","v0.6.1-alpha","v0.6.0-alpha","v0.5.0-alpha","v0.4.1-alpha","v0.4.0-alpha","v0.3.0-alpha","v0.2.0-alpha","v0.1.0-alpha"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-42273.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N"}]}