Vulnerability · Published Oct 21, 2026 · Assigned by VulnCheck

CVE-2026-114061SvelteKit before 3.0.0 XSS via Cache-Control Header in Prerendered Pages

Medium 4.7

In plain English

A medium-severity cross-site scripting in kit from sveltejs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 12% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.7Medium

Exploit odds (30 days)0.2%top 88.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

SvelteKit (@sveltejs/kit) before 3.0.0 contains a cross-site scripting vulnerability in prerendered pages because a cache-control header value set via setHeaders is inserted without escaping into a <meta http-equiv="cache-control"> tag. An attacker who can influence that untrusted value at prerender time can break out of the content attribute and inject HTML or JavaScript that executes when users visit the page.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	@sveltejs/kit	3.0.0	GHSA-27mw-82g8-phjj

Affected products (as reported)

Vendor	Product	Versions
sveltejs	kit	0 – before 3.0.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N

References

GitHub Security Advisory (GHSA-27mw-82g8-phjj) vendor-advisory
VulnCheck Advisory: SvelteKit before 3.0.0 XSS via Cache-Control Header in Prerendered Pages third-party-advisory