---
id: "CVE-2026-117947"
kind: "vulnerability"
aliases: ["CVE-2026-117947"]
title: "Firefox: use-after-free in XML component may let attackers run code"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["desktop-browsers", "firefox", "other"]
not_affected_if: []
published_at: "2026-10-27T14:16:50+00:00"
first_seen_at: "2026-10-27T14:32:23+00:00"
updated_at: "2026-10-27T14:35:41+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117947", "first_seen_at": "2026-10-27T14:32:23+00:00"}]
---

# Firefox: use-after-free in XML component may let attackers run code

A use-after-free bug in the XML component of Firefox was fixed in Firefox 159 and Firefox ESR 153.6. The sources do not say what an attacker gets beyond the memory corruption class of the flaw.

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

## Fix

- Update Firefox to `159` or later
- Update Firefox ESR to `153.6` or later

## Timeline

- 2026-10-27T14:32:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117947

## From the sources

Use-after-free in the XML component. This vulnerability was fixed in Firefox 159 and Firefox ESR 153.6.

---

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