{"cve":"CVE-2026-42567","nvd":{"published":"2026-06-09T17:17:07.100","modified":"2026-07-23T08:10:00.137","status":"Analyzed","description":"Svelte is a performance oriented web framework. From version 5.51.5 to before version 5.55.7, an internal regex in the Svelte runtime can take exponential time to test in <svelte:element this={tag}></svelte:element>. This issue has been patched in version 5.55.7.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":5.9},"cvss_v3":{"version":"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},"cwes":["CWE-1333"],"references":["https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7","https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6"],"products":["svelte:svelte"],"source":"nvd","synced_at":"2026-10-19T22:38:48.522727527+00:00"},"epss":{"cve":"CVE-2026-42567","score":0.00451,"percentile":0.3921,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-9rmh-mm8f-r9h6","url":"https://osv.dev/vulnerability/GHSA-9rmh-mm8f-r9h6","summary":"Svelte: ReDoS in `<svelte:element>` Tag Validation","modified":"2026-06-09T18:45:23.337407449Z","packages":[{"ecosystem":"npm","name":"svelte","purl":"pkg:npm/svelte","ranges":[">=5.51.5 <5.55.7"],"fixed":["5.55.7"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}