---
id: "CVE-2026-117968"
kind: "vulnerability"
aliases: ["CVE-2026-117968"]
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: "package"
products: []
ecosystems: []
tags: ["browsers", "desktop", "firefox", "package"]
not_affected_if: ["already-on-fixed-version"]
published_at: "2026-10-27T14:16:54+00:00"
first_seen_at: "2026-10-27T14:32:24+00:00"
updated_at: "2026-10-27T14:35:21+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117968", "first_seen_at": "2026-10-27T14:32:24+00:00"}]
---

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

A use-after-free bug in the DOM Core and HTML component of Firefox lets memory be reused after it is freed. The sources do not say what an attacker gets beyond that, so the reach of the flaw is unconfirmed.

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

## How to check

- Check the installed Firefox version in Help > About Firefox or with `firefox --version`, and compare it to the fixed releases.
- Check ESR installs for `115.44` or `153.6` or later.

## Fix

- Update Firefox to `159` or later.
- Update Firefox ESR 115 to `115.44` or later.
- Update Firefox ESR 153 to `153.6` or later.

## Timeline

- 2026-10-27T14:32:24+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117968

## From the sources

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

---

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