---
id: CVE-2026-79320
title: >-
  Stencil core 4.43.5 contains a DOM-based cross-site scripting (XSS)
  vulnerability in the component runtime
summary: >-
  Stencil core 4.43.5 contains a DOM-based cross-site scripting (XSS)
  vulnerability in the component runtime. When a downstream application enables
  the experimental slot fixes option and uses scoped components, assigning a
  string to the te…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
published: '2026-09-21'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T13:17:11.380'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-79320'
references:
  - url: 'https://github.com/lichoin/TraceLoom/blob/main/CVEs/CVE-2026-79320.md'
    label: cve@mitre.org
  - url: 'https://github.com/stenciljs/core'
    label: cve@mitre.org
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-24T12:48:26.689808Z'
epss: 0.00142
epssPercentile: 0.03909
ingestedAt: '2026-09-21T19:51:58.869Z'
---

## Overview

Stencil core 4.43.5 contains a DOM-based cross-site scripting (XSS) vulnerability in the component runtime. When a downstream application enables the experimental slot fixes option and uses scoped components, assigning a string to the textContent property of such a component's host element causes the value to be parsed as HTML instead of being inserted as text. If an application writes attacker-controlled data to these host elements, the data can be interpreted as markup and script can execute in the context of the application's origin.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.