In short
- CVE-2026-27122 is a MEDIUM (CVSS 5.4) vulnerability affecting svelte (svelte), svelte.
- Chance of exploitation in the next 30 days (EPSS): 0.22%, higher than 12.6% of all vulnerabilities.
- Fix: update to 5.51.5 or later.
| Package | Affected versions | Patched versions |
|---|
| svelte | < 5.51.5
| 5.51.5
|
| svelte npm | < 5.51.5
| 5.51.5
|
Description
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.
NVD description
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.
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