cve.bz

CVE-2026-66062

5.3 mediumEPSS 0.5%

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.70.2, the content negotiation header parser used by SvelteKit's request handling (for headers such as Accept) uses a regular expression vulnerable to quadratic backtracking, so a maliciously crafted header value can cause excessive CPU consumption and degrade or deny service. Version 2.70.2 fixes the issue.

CVSS 3.1
5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
0.5% chance of exploitation in the next 30 days; higher than 42% of CVEs (scores of 2026-10-25)
CWE
CWE-1333
Published
Modified
Record from
the NVD, synced

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-29g2-3rmr-qm68npm@sveltejs/kit<2.70.22.70.2

References

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