{"id":"CVE-2026-42273","state":"PUBLISHED","title":"Heimdall: Case-sensitive host matching may lead to policy bypass","description":"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.","publishedAt":"2026-05-08T03:42:50.312Z","updatedAt":"2026-05-08T10:40:56.541Z","severity":{"score":7.8,"label":"High","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["dadrus heimdall"],"affected":[{"vendor":"dadrus","product":"heimdall","versions":[{"version":"< 0.17.14","status":"affected"}]}],"references":["https://github.com/dadrus/heimdall/security/advisories/GHSA-72h4-mxfc-jx37","https://github.com/dadrus/heimdall/pull/3208","https://github.com/dadrus/heimdall/commit/3d05e56a9e7ef0355f17482b4322054af4e85943","https://github.com/dadrus/heimdall/releases/tag/v0.17.14"],"weaknesses":["CWE-436","CWE-178"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42273.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42273","state":"PUBLISHED","datePublished":"2026-05-08T03:42:50.312Z","dateUpdated":"2026-05-08T10:40:56.541Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-26T11:53:27.707Z"},"containers":{"cna":{"title":"Heimdall: Case-sensitive host matching may lead to policy bypass","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"dadrus","product":"heimdall","versions":[{"version":"< 0.17.14","status":"affected"}]}],"references":[{"url":"https://github.com/dadrus/heimdall/security/advisories/GHSA-72h4-mxfc-jx37","name":"https://github.com/dadrus/heimdall/security/advisories/GHSA-72h4-mxfc-jx37","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/dadrus/heimdall/pull/3208","name":"https://github.com/dadrus/heimdall/pull/3208","tags":["x_refsource_MISC"]},{"url":"https://github.com/dadrus/heimdall/commit/3d05e56a9e7ef0355f17482b4322054af4e85943","name":"https://github.com/dadrus/heimdall/commit/3d05e56a9e7ef0355f17482b4322054af4e85943","tags":["x_refsource_MISC"]},{"url":"https://github.com/dadrus/heimdall/releases/tag/v0.17.14","name":"https://github.com/dadrus/heimdall/releases/tag/v0.17.14","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","subAvailabilityImpact":"NONE","baseScore":7.8,"baseSeverity":"HIGH","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-436","lang":"en","description":"CWE-436: Interpretation Conflict","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-178","lang":"en","description":"CWE-178: Improper Handling of Case Sensitivity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-08T03:42:50.312Z"},"source":{"advisory":"GHSA-72h4-mxfc-jx37","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-08T10:40:38.505776Z","id":"CVE-2026-42273","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-08T10:40:56.541Z"}}]}}}