{"id":"GHSA-27v5-c462-wpq7","summary":"path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards","details":"### 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\n**Unsafe examples:**\n\n```\n/*foo-*bar-:baz\n/*a-:b-*c-:d\n/x/*a-:b/*c/y\n```\n\n**Safe examples:**\n\n```\n/*foo-:bar\n/*foo-:bar-*baz\n```\n\n### Patches\n\nUpgrade to version `8.4.0`.\n\n### Workarounds\n\nIf developers are using multiple wildcard parameters, they can check the regex output with a tool such as https://makenowjust-labs.github.io/recheck/playground/ to confirm whether a path is vulnerable.","aliases":["CVE-2026-4923"],"modified":"2026-07-17T21:04:29.464527849Z","published":"2026-03-27T22:23:52Z","database_specific":{"github_reviewed_at":"2026-03-27T22:23:52Z","nvd_published_at":"2026-03-26T19:17:08Z","cwe_ids":["CWE-1333"],"severity":"MODERATE","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/pillarjs/path-to-regexp/security/advisories/GHSA-27v5-c462-wpq7"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-4923"},{"type":"WEB","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"PACKAGE","url":"https://github.com/pillarjs/path-to-regexp"},{"type":"WEB","url":"https://makenowjust-labs.github.io/recheck/playground"}],"affected":[{"package":{"name":"path-to-regexp","ecosystem":"npm","purl":"pkg:npm/path-to-regexp"},"ranges":[{"type":"SEMVER","events":[{"introduced":"8.0.0"},{"fixed":"8.4.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-27v5-c462-wpq7/GHSA-27v5-c462-wpq7.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}