{"id":"EUVD-2026-16324","revision":null,"records":[{"revision":"8718a1ebb373450996a94b67938df4ac","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-4926","aliases":[],"title":"path-to-regexp vulnerable to Denial of Service via sequential optional groups","description":"Impact:\n\nA bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service.\n\nPatches:\n\nFixed in version 8.4.0.\n\nWorkarounds:\n\nLimit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.","state":0,"publishedAt":"2026-03-26T18:59:38+00:00","modifiedAt":"2026-09-17T12:04:38.293+00:00","affected":[{"ecosystem":"Vendor product","name":"path-to-regexp","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"path-to-regexp\",\n                    \"product\": \"path-to-regexp\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"versions\": [\n                        {\n                            \"versionType\": \"semver\",\n                            \"status\": \"affected\",\n                            \"version\": \"8.0.0\",\n                            \"lessThan\": \"8.4.0\"\n                        },\n                        {\n                            \"versionType\": \"semver\",\n                            \"status\": \"unaffected\",\n                            \"version\": \"8.4.0\"\n                        }\n                    ],\n                    \"packageURL\": \"pkg:npm/path-to-regexp\"\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://cna.openjsf.org/security-advisories.html"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-4926","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-4926","identifiers":["CVE-2026-4926"]},"retained":false,"historicalAffected":[]},{"revision":"597bfc2eab044a2489927d44547bf270","observedAt":"2026-11-11T13:03:33.47+00:00","statement":{"source":"euvd","id":"EUVD-2026-16324","aliases":["CVE-2026-4926"],"title":"Impact:","description":"Impact:\n\nA bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service.\n\nPatches:\n\nFixed in version 8.4.0.\n\nWorkarounds:\n\nLimit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":null}],"references":["https://cna.openjsf.org/security-advisories.html"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-16324","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Mar 26, 2026, 6:59:38 PM","dateUpdated":"Sep 17, 2026, 12:04:38 PM"},"relatedAdvisories":[{"id":"RHSA-2026:13545","title":"Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.6 Container Release Update","vulnerabilityIds":["CVE-2025-68121","CVE-2025-69227","CVE-2025-69228","CVE-2026-0598","CVE-2026-4800","CVE-2026-4926","CVE-2026-6266","CVE-2026-12382","CVE-2026-23490","CVE-2026-24049","CVE-2026-25679","CVE-2026-26007","CVE-2026-27137","CVE-2026-27459","CVE-2026-27606","CVE-2026-29074","CVE-2026-30922","CVE-2026-31812","CVE-2026-32274","CVE-2026-32280","CVE-2026-32597","CVE-2026-33154","CVE-2026-33810","CVE-2026-35029","CVE-2026-35030"]},{"id":"RHSA-2026:19410","title":"Red Hat Security Advisory: MTV RHEL9 Images","vulnerabilityIds":["CVE-2026-4598","CVE-2026-4599","CVE-2026-4600","CVE-2026-4601","CVE-2026-4602","CVE-2026-4800","CVE-2026-4926","CVE-2026-29063"]},{"id":"RHSA-2026:50300","title":"Red Hat Security Advisory: Migration Toolkit for Applications","vulnerabilityIds":["CVE-2026-4926","CVE-2026-12143","CVE-2026-13149","CVE-2026-25681","CVE-2026-26996","CVE-2026-27136","CVE-2026-27904","CVE-2026-33811","CVE-2026-39820","CVE-2026-39821","CVE-2026-40895","CVE-2026-42039","CVE-2026-42041","CVE-2026-42044","CVE-2026-42264","CVE-2026-42342","CVE-2026-42499","CVE-2026-42504","CVE-2026-44486","CVE-2026-44487","CVE-2026-44488","CVE-2026-44492","CVE-2026-44494","CVE-2026-44495","CVE-2026-44496","CVE-2026-55603"]},{"id":"WID-SEC-W-2026-1407","title":"IBM App Connect Enterprise Certified Container: Mehrere Schwachstellen","vulnerabilityIds":["CVE-2026-26013","CVE-2026-27142","CVE-2026-28277","CVE-2026-28684","CVE-2026-32288","CVE-2026-33151","CVE-2026-33349","CVE-2026-33532","CVE-2026-33891","CVE-2026-33894","CVE-2026-33895","CVE-2026-33896","CVE-2026-33916","CVE-2026-34601","CVE-2026-35469","CVE-2026-39406","CVE-2026-39407","CVE-2026-39408","CVE-2026-39409","CVE-2026-39410","CVE-2026-39983","CVE-2026-40175","CVE-2026-40347","CVE-2026-40895","CVE-2026-41238","CVE-2026-41239","CVE-2026-41240","CVE-2026-4923","CVE-2026-4926"]},{"id":"RHSA-2026:10175","title":"Red Hat Security Advisory: Red Hat OpenShift Dev Spaces 3.27.1 Release.","vulnerabilityIds":["CVE-2025-61728","CVE-2025-62718","CVE-2026-2332","CVE-2026-4800","CVE-2026-4926","CVE-2026-22731","CVE-2026-25679","CVE-2026-26999","CVE-2026-27137","CVE-2026-27606","CVE-2026-29054","CVE-2026-32305","CVE-2026-32695","CVE-2026-33186","CVE-2026-33433","CVE-2026-33805","CVE-2026-33870","CVE-2026-33871","CVE-2026-33937","CVE-2026-33938","CVE-2026-33939","CVE-2026-33940","CVE-2026-33941","CVE-2026-34986","CVE-2026-40175"]},{"id":"RHSA-2026:13826","title":"Red Hat Security Advisory: Red Hat Developer Hub 1.9.4 release.","vulnerabilityIds":["CVE-2025-62718","CVE-2025-69534","CVE-2026-1525","CVE-2026-1526","CVE-2026-1528","CVE-2026-2229","CVE-2026-3118","CVE-2026-4800","CVE-2026-4926","CVE-2026-27601","CVE-2026-27904","CVE-2026-29063","CVE-2026-29074","CVE-2026-29186","CVE-2026-32141","CVE-2026-32280","CVE-2026-32282","CVE-2026-33228","CVE-2026-33891","CVE-2026-33894","CVE-2026-33895","CVE-2026-33896","CVE-2026-39983","CVE-2026-40175","CVE-2026-40895"]},{"id":"RHSA-2026:10153","title":"Red Hat Security Advisory: RHTAS 1.3.4 - Red Hat Trusted Artifact Signer Release","vulnerabilityIds":["CVE-2026-4926","CVE-2026-33186","CVE-2026-40175"]},{"id":"RHSA-2026:24762","title":"Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.6 Product Security and Bug Fix Update","vulnerabilityIds":["CVE-2026-4800","CVE-2026-4926","CVE-2026-7246","CVE-2026-30922","CVE-2026-32280","CVE-2026-32282","CVE-2026-32283","CVE-2026-33891","CVE-2026-39363","CVE-2026-39892","CVE-2026-40175","CVE-2026-40192"]},{"id":"RHSA-2026:40118","title":"Red Hat Security Advisory: Red Hat Edge Manager Version 1.1.3 Security Update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-61729","CVE-2025-68121","CVE-2025-69873","CVE-2026-4800","CVE-2026-4926","CVE-2026-6322","CVE-2026-13676","CVE-2026-22029","CVE-2026-25679","CVE-2026-29063","CVE-2026-32141","CVE-2026-32280","CVE-2026-32281","CVE-2026-32282","CVE-2026-33186","CVE-2026-33810","CVE-2026-33811","CVE-2026-33816","CVE-2026-39821","CVE-2026-39828","CVE-2026-39829","CVE-2026-39830","CVE-2026-39832","CVE-2026-39835","CVE-2026-42151","CVE-2026-42154","CVE-2026-42508","CVE-2026-46595"]},{"id":"RHSA-2026:9742","title":"Red Hat Security Advisory: Red Hat Developer Hub 1.8.6 release.","vulnerabilityIds":["CVE-2025-62718","CVE-2025-69534","CVE-2025-69873","CVE-2026-1525","CVE-2026-1526","CVE-2026-1528","CVE-2026-2229","CVE-2026-3118","CVE-2026-4800","CVE-2026-4926","CVE-2026-25679","CVE-2026-26996","CVE-2026-27601","CVE-2026-27904","CVE-2026-29063","CVE-2026-29074","CVE-2026-29186","CVE-2026-32141","CVE-2026-33036","CVE-2026-33228","CVE-2026-33891","CVE-2026-33894","CVE-2026-33895","CVE-2026-33896","CVE-2026-39983","CVE-2026-40175"]},{"id":"RHSA-2026:19409","title":"Red Hat Security Advisory: MTV RHEL9 Images","vulnerabilityIds":["CVE-2026-4598","CVE-2026-4599","CVE-2026-4600","CVE-2026-4601","CVE-2026-4602","CVE-2026-4800","CVE-2026-4926","CVE-2026-29063"]},{"id":"RHSA-2026:40945","title":"Red Hat Security Advisory: Red Hat Edge Manager Version 1.1.3 Security Update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-61729","CVE-2025-68121","CVE-2025-69873","CVE-2026-4800","CVE-2026-4926","CVE-2026-6322","CVE-2026-13676","CVE-2026-22029","CVE-2026-25679","CVE-2026-29063","CVE-2026-32141","CVE-2026-32280","CVE-2026-32281","CVE-2026-32282","CVE-2026-33186","CVE-2026-33810","CVE-2026-33811","CVE-2026-33816","CVE-2026-39821","CVE-2026-39828","CVE-2026-39829","CVE-2026-39830","CVE-2026-39832","CVE-2026-39835","CVE-2026-42151","CVE-2026-42154","CVE-2026-42508","CVE-2026-46595"]},{"id":"WID-SEC-W-2026-3046","title":"IBM Concert: Mehrere Schwachstellen","vulnerabilityIds":["CVE-2019-19921","CVE-2021-23337","CVE-2024-3651","CVE-2024-39338","CVE-2024-45590","CVE-2025-13465","CVE-2025-15284","CVE-2025-15599","CVE-2025-22874","CVE-2025-47273","CVE-2025-47907","CVE-2025-52881","CVE-2025-53643","CVE-2025-55184","CVE-2025-58056","CVE-2025-58188","CVE-2025-58189","CVE-2025-61723","CVE-2025-61730","CVE-2025-64649","CVE-2025-64756","CVE-2025-67221","CVE-2025-68121","CVE-2025-68146","CVE-2026-0540","CVE-2026-2327","CVE-2026-23490","CVE-2026-23897","CVE-2026-2391","CVE-2026-23949","CVE-2026-24486","CVE-2026-25528","CVE-2026-25547","CVE-2026-25639","CVE-2026-25990","CVE-2026-26007","CVE-2026-26019","CVE-2026-26996","CVE-2026-27142","CVE-2026-27212","CVE-2026-27699","CVE-2026-27903","CVE-2026-27904","CVE-2026-28684","CVE-2026-29063","CVE-2026-29181","CVE-2026-2950","CVE-2026-31808","CVE-2026-31900","CVE-2026-32274","CVE-2026-32288","CVE-2026-32597","CVE-2026-32630","CVE-2026-32887","CVE-2026-32952","CVE-2026-33186","CVE-2026-33532","CVE-2026-33750","CVE-2026-33814","CVE-2026-33816","CVE-2026-33916","CVE-2026-34043","CVE-2026-34073","CVE-2026-34077","CVE-2026-3520","CVE-2026-35469","CVE-2026-35515","CVE-2026-3627","CVE-2026-39823","CVE-2026-39825","CVE-2026-39826","CVE-2026-39892","CVE-2026-39984","CVE-2026-40175","CVE-2026-40179","CVE-2026-40181","CVE-2026-40190","CVE-2026-40347","CVE-2026-41066","CVE-2026-41182","CVE-2026-41238","CVE-2026-41239","CVE-2026-41240","CVE-2026-41305","CVE-2026-41324","CVE-2026-41425","CVE-2026-41481","CVE-2026-41488","CVE-2026-41602","CVE-2026-41636","CVE-2026-42151","CVE-2026-42154","CVE-2026-42198","CVE-2026-42211","CVE-2026-42338","CVE-2026-42342","CVE-2026-42561","CVE-2026-42577","CVE-2026-43870","CVE-2026-44405","CVE-2026-44431","CVE-2026-44432","CVE-2026-44486","CVE-2026-44487","CVE-2026-44488","CVE-2026-44492","CVE-2026-44494","CVE-2026-44496","CVE-2026-44728","CVE-2026-4539","CVE-2026-45409","CVE-2026-45736","CVE-2026-46625","CVE-2026-4800","CVE-2026-4923","CVE-2026-4926","CVE-2026-7246","CVE-2026-8723"]},{"id":"RHSA-2026:17789","title":"Red Hat Security Advisory: Red Hat build of Cryostat 4.2.0: new RHEL 9 container image security update","vulnerabilityIds":["CVE-2026-1002","CVE-2026-1525","CVE-2026-1526","CVE-2026-1528","CVE-2026-2229","CVE-2026-4800","CVE-2026-4926","CVE-2026-33186","CVE-2026-33813","CVE-2026-33815","CVE-2026-33816","CVE-2026-33870","CVE-2026-33871","CVE-2026-34986","CVE-2026-39852","CVE-2026-40895"]},{"id":"RHSA-2026:65126","title":"Red Hat Security Advisory: RHOAI 2.25.11 - Red Hat OpenShift AI","vulnerabilityIds":["CVE-2025-61729","CVE-2025-67030","CVE-2026-4926","CVE-2026-6734","CVE-2026-9563","CVE-2026-9697","CVE-2026-12151","CVE-2026-12243","CVE-2026-13149","CVE-2026-15075","CVE-2026-15154","CVE-2026-15378","CVE-2026-15581","CVE-2026-16745","CVE-2026-18608","CVE-2026-18611","CVE-2026-18617","CVE-2026-18620","CVE-2026-18621","CVE-2026-25681","CVE-2026-26996","CVE-2026-27136","CVE-2026-27904","CVE-2026-30922","CVE-2026-32283","CVE-2026-33231","CVE-2026-33810","CVE-2026-33811","CVE-2026-33814","CVE-2026-33870","CVE-2026-33871","CVE-2026-34445","CVE-2026-35536","CVE-2026-39821","CVE-2026-39829","CVE-2026-39835","CVE-2026-40171","CVE-2026-40192","CVE-2026-40895","CVE-2026-41178","CVE-2026-42027","CVE-2026-42215","CVE-2026-42284","CVE-2026-42338","CVE-2026-42502","CVE-2026-42508","CVE-2026-42578","CVE-2026-42579","CVE-2026-42581","CVE-2026-42583","CVE-2026-42584","CVE-2026-42587","CVE-2026-44240","CVE-2026-44244","CVE-2026-44249","CVE-2026-44431","CVE-2026-44893","CVE-2026-45112","CVE-2026-45416","CVE-2026-45623","CVE-2026-45674","CVE-2026-45736","CVE-2026-45819","CVE-2026-47691","CVE-2026-48043","CVE-2026-48059","CVE-2026-48586","CVE-2026-48779","CVE-2026-49978","CVE-2026-50010","CVE-2026-50193","CVE-2026-53550","CVE-2026-54293","CVE-2026-54512","CVE-2026-55685","CVE-2026-55831","CVE-2026-55833","CVE-2026-55851","CVE-2026-56745","CVE-2026-56746","CVE-2026-56819","CVE-2026-56853","CVE-2026-56858","CVE-2026-56859","CVE-2026-56860","CVE-2026-56862","CVE-2026-59869","CVE-2026-59873","CVE-2026-59874","CVE-2026-59885","CVE-2026-59899","CVE-2026-66036","CVE-2026-66039","CVE-2026-67313","CVE-2026-67320","CVE-2026-67322","CVE-2026-67323","CVE-2026-67324","CVE-2026-67325","CVE-2026-68494","CVE-2026-69112","CVE-2026-69152","CVE-2026-69192","CVE-2026-69243","CVE-2026-69244","CVE-2026-71281","CVE-2026-73088","CVE-2026-73089","CVE-2026-73415","CVE-2026-73417","CVE-2026-73566","CVE-2026-73622","CVE-2026-73623","CVE-2026-73624","CVE-2026-73625","CVE-2026-73627","CVE-2026-73643"]},{"id":"RHSA-2026:24866","title":"Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.6 Container Release Update","vulnerabilityIds":["CVE-2025-62718","CVE-2026-4926","CVE-2026-6321","CVE-2026-23490","CVE-2026-28390","CVE-2026-28684","CVE-2026-33154","CVE-2026-39363","CVE-2026-39364","CVE-2026-39892","CVE-2026-40192","CVE-2026-40217","CVE-2026-41140","CVE-2026-48710"]},{"id":"RHSA-2026:9385","title":"Red Hat Security Advisory: Red Hat OpenShift distributed tracing platform (Tempo) 3.9.2 release","vulnerabilityIds":["CVE-2025-68121","CVE-2026-4645","CVE-2026-4800","CVE-2026-4926","CVE-2026-25679","CVE-2026-27137","CVE-2026-32280","CVE-2026-32282","CVE-2026-32285","CVE-2026-33186","CVE-2026-33810","CVE-2026-34986"]},{"id":"RHSA-2026:24761","title":"Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.5 Product Security and Bug Fix Update","vulnerabilityIds":["CVE-2025-62718","CVE-2026-4926","CVE-2026-7246","CVE-2026-26996","CVE-2026-27904","CVE-2026-30922","CVE-2026-32280","CVE-2026-32282","CVE-2026-32283","CVE-2026-33891","CVE-2026-33894","CVE-2026-33895","CVE-2026-33896","CVE-2026-39363","CVE-2026-39892","CVE-2026-40192"]},{"id":"RHSA-2026:10172","title":"Red Hat Security Advisory: RHTAS 1.3.4 - Red Hat Trusted Artifact Signer Release","vulnerabilityIds":["CVE-2026-4926","CVE-2026-33186","CVE-2026-40175"]},{"id":"RHSA-2026:36651","title":"Red Hat Security Advisory: Red Hat Edge Manager Version 1.0.3 Security Update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-61729","CVE-2025-68121","CVE-2025-69873","CVE-2026-4800","CVE-2026-4926","CVE-2026-6322","CVE-2026-22029","CVE-2026-25679","CVE-2026-29063","CVE-2026-32141","CVE-2026-32280","CVE-2026-33186","CVE-2026-33810","CVE-2026-33811","CVE-2026-39821","CVE-2026-39828","CVE-2026-39829","CVE-2026-39830","CVE-2026-39832","CVE-2026-39835","CVE-2026-42151","CVE-2026-42154","CVE-2026-42508","CVE-2026-46595"]}],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-16324","identifiers":["EUVD-2026-16324","CVE-2026-4926"]},"retained":false,"historicalAffected":[]},{"revision":"8c471d3383a744f9947e591147837267","observedAt":"2026-10-25T12:17:32.273+00:00","statement":{"source":"nvd","id":"CVE-2026-4926","aliases":[],"title":"Impact:","description":"Impact:\n\nA bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service.\n\nPatches:\n\nFixed in version 8.4.0.\n\nWorkarounds:\n\nLimit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.","state":0,"publishedAt":"2026-03-26T19:17:08.387+00:00","modifiedAt":"2026-09-09T13:20:25.32+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · ce714d77-add3-4f53-aff5-83d477b104bb · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"},{"system":"CVSS 3.1 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://cna.openjsf.org/security-advisories.html","https://access.redhat.com/errata/RHSA-2026:10153","https://access.redhat.com/errata/RHSA-2026:10172","https://access.redhat.com/errata/RHSA-2026:10175","https://access.redhat.com/errata/RHSA-2026:13545","https://access.redhat.com/errata/RHSA-2026:13826","https://access.redhat.com/errata/RHSA-2026:17789","https://access.redhat.com/errata/RHSA-2026:19409","https://access.redhat.com/errata/RHSA-2026:19410","https://access.redhat.com/errata/RHSA-2026:24761","https://access.redhat.com/errata/RHSA-2026:24762","https://access.redhat.com/errata/RHSA-2026:24866","https://access.redhat.com/errata/RHSA-2026:36651","https://access.redhat.com/errata/RHSA-2026:40118","https://access.redhat.com/errata/RHSA-2026:40945","https://access.redhat.com/errata/RHSA-2026:50300","https://access.redhat.com/errata/RHSA-2026:65126","https://access.redhat.com/errata/RHSA-2026:9385","https://access.redhat.com/errata/RHSA-2026:9742","https://access.redhat.com/security/cve/CVE-2026-4926","https://bugzilla.redhat.com/show_bug.cgi?id=2451867","https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4926.json"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-4926","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Modified","weaknesses":["CWE-400","CWE-1333"],"productCriteria":["cpe:2.3:a:pillarjs:path-to-regexp:*:*:*:*:*:node.js:*:*"],"sourceDates":{"published":"2026-03-26T19:17:08.387","lastModified":"2026-09-09T13:20:25.320"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. 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