---
id: "CVE-2026-118007"
kind: "vulnerability"
aliases: ["CVE-2026-118007"]
title: "Firefox: use-after-free in JavaScript garbage collector fixed in 159"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browser", "desktop", "firefox", "runtime"]
not_affected_if: ["firefox-159-or-later"]
published_at: "2026-10-27T14:16:58+00:00"
first_seen_at: "2026-10-27T14:32:25+00:00"
updated_at: "2026-10-27T14:33:38+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118007", "first_seen_at": "2026-10-27T14:32:25+00:00"}]
---

# Firefox: use-after-free in JavaScript garbage collector fixed in 159

A use-after-free bug in the JavaScript garbage collector of Firefox can corrupt memory when the browser runs certain scripts. The sources do not say what an attacker can achieve beyond that, and the description says the issue was fixed in Firefox 159.

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

## How to check

- Run `Help > About Firefox` in the browser and compare the version with `159`.
- unknown

## Fix

- Update Firefox to `159` or later.

## Timeline

- 2026-10-27T14:32:25+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-118007

## From the sources

Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 159.

---

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