---
id: "CVE-2026-117930"
kind: "vulnerability"
aliases: ["CVE-2026-117930"]
title: "Firefox: use-after-free in DOM bindings can crash or 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: "2026-10-27T14:37:07+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117930", "first_seen_at": "2026-10-27T14:32:23+00:00"}]
---

# Firefox: use-after-free in DOM bindings can crash or run code

A use-after-free bug in the DOM Bindings (WebIDL) component of Firefox lets memory be reused after it is freed. The sources do not say what an attacker can achieve beyond that, so the exact impact is unclear.

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

## How to check

- Run `firefox --version` or open About Firefox and compare against `159`, `115.44` (ESR) and `153.6` (ESR)
- Check whether the installed version is older than the fixed release for its branch

## Fix

- Update Firefox to `159`, or to `115.44` on the ESR 115 branch, or to `153.6` on the ESR 153 branch

## Timeline

- 2026-10-27T14:32:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117930

## From the sources

Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

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