---
id: "CVE-2026-117960"
kind: "vulnerability"
aliases: ["CVE-2026-117960"]
title: "Firefox: DOM spoofing flaw in Core and HTML component, fixed"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["browser", "desktop", "firefox", "other"]
not_affected_if: ["already-updated-to-159-or-153.6"]
published_at: "2026-10-27T14:16:52+00:00"
first_seen_at: "2026-10-27T14:32:24+00:00"
updated_at: "2026-10-27T14:35:29+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117960", "first_seen_at": "2026-10-27T14:32:24+00:00"}]
---

# Firefox: DOM spoofing flaw in Core and HTML component, fixed

A spoofing flaw in the DOM Core and HTML component of Firefox lets a page present misleading content to the user. The sources do not say what exact content can be spoofed or what an attacker gains beyond that.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Firefox version in the browser's About menu or with `firefox --version`; releases before `159` and ESR before `153.6` are the ones named as fixed.
- unknown for other checks, the sources do not say.

## Fix

- Update Firefox to `159` or later, or Firefox ESR to `153.6` or later.

## Timeline

- 2026-10-27T14:32:24+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117960

## From the sources

Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159 and Firefox ESR 153.6.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_