{"id":"CVE-2026-59897","state":"PUBLISHED","title":"Hono: API Gateway v1 adapter can drop a distinct repeated request header value during de-duplication","description":"Hono is a Web application framework that provides support for any JavaScript runtime. From 4.3.3 before 4.12.27, the AWS API Gateway v1 adapter can drop a distinct repeated request header value because it de-duplicates values using a substring comparison instead of an exact match, so middleware or application logic that depends on the complete X-Forwarded-For chain, rate limiting, audit logging, or proxy-chain validation can receive incomplete data. This issue is fixed in version 4.12.27.","publishedAt":"2026-07-08T16:06:11.369Z","updatedAt":"2026-07-09T13:51:31.335Z","severity":{"score":4.8,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["honojs hono"],"affected":[{"vendor":"honojs","product":"hono","versions":[{"version":">= 4.3.3, < 4.12.27","status":"affected"}]}],"references":["https://github.com/honojs/hono/security/advisories/GHSA-xgm2-5f3f-mvvc","https://github.com/honojs/hono/commit/aa921770d09bc35970362d5a2630a878f6d982fd","https://github.com/honojs/hono/releases/tag/v4.12.27"],"weaknesses":["CWE-348"],"ingestedAt":"2026-10-29T20:12:32.778Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/59xxx/CVE-2026-59897.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-59897","state":"PUBLISHED","datePublished":"2026-07-08T16:06:11.369Z","dateUpdated":"2026-07-09T13:51:31.335Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-07T16:40:07.984Z"},"containers":{"cna":{"title":"Hono: API Gateway v1 adapter can drop a distinct repeated request header value during de-duplication","descriptions":[{"lang":"en","value":"Hono is a Web application framework that provides support for any JavaScript runtime. From 4.3.3 before 4.12.27, the AWS API Gateway v1 adapter can drop a distinct repeated request header value because it de-duplicates values using a substring comparison instead of an exact match, so middleware or application logic that depends on the complete X-Forwarded-For chain, rate limiting, audit logging, or proxy-chain validation can receive incomplete data. This issue is fixed in version 4.12.27."}],"affected":[{"vendor":"honojs","product":"hono","versions":[{"version":">= 4.3.3, < 4.12.27","status":"affected"}]}],"references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-xgm2-5f3f-mvvc","name":"https://github.com/honojs/hono/security/advisories/GHSA-xgm2-5f3f-mvvc","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/honojs/hono/commit/aa921770d09bc35970362d5a2630a878f6d982fd","name":"https://github.com/honojs/hono/commit/aa921770d09bc35970362d5a2630a878f6d982fd","tags":["x_refsource_MISC"]},{"url":"https://github.com/honojs/hono/releases/tag/v4.12.27","name":"https://github.com/honojs/hono/releases/tag/v4.12.27","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.8,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-348","lang":"en","description":"CWE-348: Use of Less Trusted Source","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-08T16:06:11.369Z"},"source":{"advisory":"GHSA-xgm2-5f3f-mvvc","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-09T13:51:23.283182Z","id":"CVE-2026-59897","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-09T13:51:31.335Z"}}]}}}