---
id: "CVE-2026-117932"
kind: "vulnerability"
aliases: ["CVE-2026-117932"]
title: "Firefox: use-after-free in DOM core and HTML lets attackers run code"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browsers", "desktop", "firefox", "runtime"]
not_affected_if: ["already-on-fixed-version"]
published_at: "2026-10-27T14:16:48+00:00"
first_seen_at: "2026-10-27T14:32:23+00:00"
updated_at: "2026-10-27T14:37:06+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117932", "first_seen_at": "2026-10-27T14:32:23+00:00"}]
---

# Firefox: use-after-free in DOM core and HTML lets attackers run code

A use-after-free flaw in the DOM Core and HTML component of Firefox was fixed in Firefox 159 and Firefox ESR 153.6. The sources do not state the attacker's exact gain, but use-after-free bugs in browser engines are commonly abused to run code.

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

## How to check

- Open the Firefox version under Help > About Firefox, or run `firefox --version` on the machine
- Check whether the installed version is below `159` (Firefox) or `153.6` (Firefox ESR)

## Fix

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

## Timeline

- 2026-10-27T14:32:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117932

## From the sources

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159 and Firefox ESR 153.6.

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