CVE-2026-27122

svelte performance oriented web framework. Prior to 5.51.5, when using <svelte:element this={tag}> in…

CVSS 4.0 · [email protected] · Secondary 5.1 MEDIUMCVSS 3.1 · [email protected] · Primary 5.4 MEDIUMCheck source for fixed versionsKEV status unknown

Original advisory

Historical advisory recorded 25 Oct 2026 06:17:28 UTC. Read the latest advisory.

nvd · CVE-2026-27122

Published

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.

Read the publisher's advisory

Affected versions, risk and source history

nvd · CVE-2026-27122

Published

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 co…

Additional publisher context

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Analyzed

Weakness classifications: CWE-79

Original publisher date fields

published: 2026-02-20T23:16:02.640

lastModified: 2026-06-17T10:26:42.403

1 source CPE criteria · context only

cpe:2.3:a:svelte:svelte:*:*:*:*:*:node.js:*:*

The original JSON retains the logical configuration operators, exclusions and version bounds.

Source published: 20 Feb 2026 23:16:02 UTC
Source modified: 17 Jun 2026 10:26:42 UTC
Saved here: 25 Oct 2026 06:17:28 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 4.0 · [email protected] · Secondary · 5.1 CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS 3.1 · [email protected] · Primary · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N