{"id":"CVE-2026-4923","state":"PUBLISHED","title":"path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards","description":"Impact:\n\nWhen using multiple wildcards, combined with at least one parameter, a regular expression can be generated that is vulnerable to ReDoS. This backtracking vulnerability requires the second wildcard to be somewhere other than the end of the path.\n\nUnsafe examples:\n\n/*foo-*bar-:baz\n/*a-:b-*c-:d\n/x/*a-:b/*c/y\n\nSafe examples:\n\n/*foo-:bar\n/*foo-:bar-*baz\n\nPatches:\n\nUpgrade to version 8.4.0.\n\nWorkarounds:\n\nIf you are using multiple wildcard parameters, you can check the regex output with a tool such as https://makenowjust-labs.github.io/recheck/playground/ to confirm whether a path is vulnerable.","publishedAt":"2026-03-26T19:02:00.729Z","updatedAt":"2026-03-27T13:58:03.925Z","severity":{"score":5.9,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"openjs"},"assigner":"openjs","products":["path-to-regexp path-to-regexp"],"affected":[{"vendor":"path-to-regexp","product":"path-to-regexp","packageURL":"pkg:npm/path-to-regexp","defaultStatus":"unaffected","versions":[{"version":"8.0.0","status":"affected","lessThan":"8.4.0","versionType":"semver"},{"version":"8.4.0","status":"unaffected","versionType":"semver"}]}],"references":["https://cna.openjsf.org/security-advisories.html"],"weaknesses":["CWE-1333"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/4xxx/CVE-2026-4923.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-4923","state":"PUBLISHED","datePublished":"2026-03-26T19:02:00.729Z","dateUpdated":"2026-03-27T13:58:03.925Z","assignerShortName":"openjs","assignerOrgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateReserved":"2026-03-26T18:05:44.717Z"},"containers":{"cna":{"title":"path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards","descriptions":[{"lang":"en","value":"Impact:\n\nWhen using multiple wildcards, combined with at least one parameter, a regular expression can be generated that is vulnerable to ReDoS. This backtracking vulnerability requires the second wildcard to be somewhere other than the end of the path.\n\nUnsafe examples:\n\n/*foo-*bar-:baz\n/*a-:b-*c-:d\n/x/*a-:b/*c/y\n\nSafe examples:\n\n/*foo-:bar\n/*foo-:bar-*baz\n\nPatches:\n\nUpgrade to version 8.4.0.\n\nWorkarounds:\n\nIf you are using multiple wildcard parameters, you can check the regex output with a tool such as https://makenowjust-labs.github.io/recheck/playground/ to confirm whether a path is vulnerable."}],"affected":[{"vendor":"path-to-regexp","product":"path-to-regexp","packageURL":"pkg:npm/path-to-regexp","defaultStatus":"unaffected","versions":[{"version":"8.0.0","status":"affected","lessThan":"8.4.0","versionType":"semver"},{"version":"8.4.0","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://cna.openjsf.org/security-advisories.html"}],"metrics":[{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.9,"baseSeverity":"MEDIUM"},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1333","lang":"en","description":"CWE-1333: Inefficient Regular Expression Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"openjs","orgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateUpdated":"2026-03-26T19:02:00.729Z"},"credits":[{"lang":"en","type":"remediation developer","value":"blakeembrey"},{"lang":"en","type":"remediation reviewer","value":"UlisesGascon"}],"x_generator":{"engine":"cve-kit 1.0.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-27T13:46:47.360477Z","id":"CVE-2026-4923","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":"2026-03-27T13:58:03.925Z"}}]}}}