{"id":"CVE-2026-42567","aliases":["GHSA-9rmh-mm8f-r9h6"],"url":"https://o3.security/vulnerability/CVE-2026-42567","summary":"Svelte: ReDoS in `<svelte:element>` Tag Validation","details":"An internal regex in the Svelte runtime can take exponential time to test in `<svelte:element this={tag}></svelte:element>`. You are only vulnerable to this if you allow tags of unconstrained length. If your application only allows a predetermined list of tags or trims their length before passing them to `svelte:element`, you are safe.","published":"2026-06-09T16:22:22.703Z","modified":"2026-08-12T03:51:47.549547556Z","cvss":null,"epss":{"score":0.00421,"percentile":0.35206,"asOf":"2026-08-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"svelte","fixedVersion":"5.55.7"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42567.json"},{"type":"ADVISORY","url":"https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42567"},{"type":"PACKAGE","url":"https://github.com/sveltejs/svelte"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:47.549547556Z"}}