PT-2026-41132 · Npm · Svelte

Published 2026-05-14 · Updated 2026-05-14 · CVE-2026-42567

OSV

CVSS v4.0

5.9

Medium

Base vector

AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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.

Fix

DoS

Weakness Enumeration

CWE-1333

Related Identifiers

CVE-2026-42567

GHSA-9RMH-MM8F-R9H6

Affected Products

Svelte

References · 4

• https://osv.dev/vulnerability/GHSA-9rmh-mm8f-r9h6 · Vendor Advisory
• https://github.com/sveltejs/svelte · Note
• https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6 · Note
• https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7 · Note