CVE-2026-27122 — Svelte SSR does not validate dynamic element tag names in `<svelte:element>`

CVE-2026-27122

Svelte SSR does not validate dynamic element tag names in `<svelte:element>` PUBLISHED

Description (CNA)

svelte performance oriented web framework. Prior to 5.51.5, when using <svelte:element this={tag}> in server-side rendering, the provided tag name is not validated or sanitized before being emitted into the HTML output. If the tag string contains unexpected characters, it can result in HTML injection in the SSR output. Client-side rendering is not affected. This vulnerability is fixed in 5.51.5.

Affected (CNA)

Vendor / product	Versions
sveltejs / svelte	affected < 5.51.5

CWE

CWE-79

References

https://github.com/sveltejs/svelte/security/advisories/GHSA-m56q-vw4c-c2cp

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.