---
id: "CVE-2026-117876"
kind: "vulnerability"
aliases: ["CVE-2026-117876"]
title: "Firefox: use-after-free in text layout and fonts code"
severity: "high"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browsers", "desktop", "firefox", "managed-fleet", "runtime"]
not_affected_if: ["already-updated-browser"]
published_at: "2026-10-27T14:16:42+00:00"
first_seen_at: "2026-10-27T14:32:21+00:00"
updated_at: "2026-10-27T14:39:10+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117876", "first_seen_at": "2026-10-27T14:32:21+00:00"}]
---

# Firefox: use-after-free in text layout and fonts code

A use-after-free bug in Firefox's Layout: Text and Fonts component lets memory be reused after it is freed. An attacker who gets a user to load a crafted page could potentially crash the browser or run code in it.

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

## How to check

- Check the Firefox version with `firefox --version` or Help > About Firefox
- Compare the installed version against the fixed releases listed in the fix field
- unknown

## 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

- 2026-10-27T14:32:21+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117876

## From the sources

Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

---

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