---
id: "CVE-2026-117971"
kind: "vulnerability"
aliases: ["CVE-2026-117971"]
title: "Firefox: use-after-free in Print Preview lets a page escape the sandbox"
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: "2026-10-27T14:16:55+00:00"
first_seen_at: "2026-10-27T14:32:24+00:00"
updated_at: "2026-10-27T14:35:18+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117971", "first_seen_at": "2026-10-27T14:32:24+00:00"}]
---

# Firefox: use-after-free in Print Preview lets a page escape the sandbox

A use-after-free bug in Firefox's Print Preview component allows content to escape the browser sandbox. Fixed in Firefox 159 and Firefox ESR 115.44 and 153.6.

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

## How to check

- `firefox --version` on desktop installs, compare against `159`, `115.44` or `153.6`
- Check the Firefox About dialog or enterprise software inventory for the installed build

## Fix

- Update Firefox to `159` or to ESR `115.44` or `153.6`, whichever matches the installed branch

## Timeline

- 2026-10-27T14:32:24+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117971

## From the sources

Sandbox escape due to use-after-free in the Print Preview component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

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