---
id: "CVE-2026-117948"
kind: "vulnerability"
aliases: ["CVE-2026-117948"]
title: "Firefox: use-after-free in SVG component can crash or run code"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["browsers", "desktop", "firefox", "other"]
not_affected_if: ["already-on-fixed-version"]
published_at: "2026-10-27T14:16:50+00:00"
first_seen_at: "2026-10-27T14:32:23+00:00"
updated_at: "2026-10-27T14:35:40+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117948", "first_seen_at": "2026-10-27T14:32:23+00:00"}]
---

# Firefox: use-after-free in SVG component can crash or run code

A use-after-free bug in Firefox's SVG handling lets a malicious page reuse freed memory. Depending on the attacker's control over that memory, this can crash the browser or let an attacker run code in it.

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

## How to check

- Run `firefox --version` (or check Help > About) and compare against `159` for Firefox or `115.44` / `153.6` for ESR.
- On managed fleets, check the installed Firefox version in your endpoint management tool.

## Fix

- Update Firefox to `159` or later.
- Update Firefox ESR to `115.44` or `153.6`, or later in the same branch.

## Timeline

- 2026-10-27T14:32:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117948

## From the sources

Use-after-free in the SVG component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

---

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