{"id":"UBUNTU-CVE-2026-4923","details":"Impact: When 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. Unsafe examples: /*foo-*bar-:baz /*a-:b-*c-:d /x/*a-:b/*c/y Safe examples: /*foo-:bar /*foo-:bar-*baz Patches: Upgrade to version 8.4.0. Workarounds: If 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confirm whether a path is vulnerable.","modified":"2026-05-21T12:15:12.234646202Z","published":"2026-03-26T19:17:00Z","withdrawn":"2026-05-21T12:08:04Z","upstream":["CVE-2026-4923"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-4923"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-4923"},{"type":"REPORT","url":"https://github.com/pillarjs/path-to-regexp/security/advisories/GHSA-27v5-c462-wpq7"},{"type":"REPORT","url":"https://cna.openjsf.org/security-advisories.html"}],"affected":[{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.1-1"],"ecosystem_specific":{"binaries":[{"binary_name":"node-path-to-regexp","binary_version":"1.0.1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}},{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.1-1"],"ecosystem_specific":{"binaries":[{"binary_name":"node-path-to-regexp","binary_version":"1.0.1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}},{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.0.0-2","3.1.0-1","6.1.0-2"],"ecosystem_specific":{"binaries":[{"binary_version":"6.1.0-2","binary_name":"node-path-to-regexp"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}},{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.2.0-1","6.2.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"node-path-to-regexp","binary_version":"6.2.0-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}},{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.2.1-1"],"ecosystem_specific":{"binaries":[{"binary_name":"node-path-to-regexp","binary_version":"6.2.1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}},{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.3.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"6.3.0-1","binary_name":"node-path-to-regexp"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}},{"package":{"name":"node-path-to-regexp","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/node-path-to-regexp?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.3.0-1","8.3.0-1","8.4.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"8.4.0-1","binary_name":"node-path-to-regexp"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-4923.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}