{"id":"CVE-2026-54286","state":"PUBLISHED","title":"Hono: Path traversal in `serve-static` on Windows via encoded backslash (`%5C`)","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on Windows hosts, an encoded backslash (%5C) in the request path decodes to \\, which the Windows path resolver treats as a separator. serve-static then resolves a single URL segment such as admin\\secret.txt into a nested file under the root and serves it, letting an attacker read static files meant to be protected behind prefix-mounted middleware. This vulnerability is fixed in 4.12.25.","publishedAt":"2026-06-22T17:14:40.133Z","updatedAt":"2026-06-23T14:07:34.188Z","severity":{"score":5.9,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["honojs hono"],"affected":[{"vendor":"honojs","product":"hono","versions":[{"version":"< 4.12.25","status":"affected"}]}],"references":["https://github.com/honojs/hono/security/advisories/GHSA-wwfh-h76j-fc44"],"weaknesses":["CWE-22"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/54xxx/CVE-2026-54286.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-54286","state":"PUBLISHED","datePublished":"2026-06-22T17:14:40.133Z","dateUpdated":"2026-06-23T14:07:34.188Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-12T17:46:37.292Z"},"containers":{"cna":{"title":"Hono: Path traversal in `serve-static` on Windows via encoded backslash (`%5C`)","descriptions":[{"lang":"en","value":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on Windows hosts, an encoded backslash (%5C) in the request path decodes to \\, which the Windows path resolver treats as a separator. serve-static then resolves a single URL segment such as admin\\secret.txt into a nested file under the root and serves it, letting an attacker read static files meant to be protected behind prefix-mounted middleware. This vulnerability is fixed in 4.12.25."}],"affected":[{"vendor":"honojs","product":"hono","versions":[{"version":"< 4.12.25","status":"affected"}]}],"references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-wwfh-h76j-fc44","name":"https://github.com/honojs/hono/security/advisories/GHSA-wwfh-h76j-fc44","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.9,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-22","lang":"en","description":"CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-22T17:14:40.133Z"},"source":{"advisory":"GHSA-wwfh-h76j-fc44","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-23T14:07:25.570505Z","id":"CVE-2026-54286","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":"2026-06-23T14:07:34.188Z"}}]}}}