---
id: "CVE-2026-117937"
kind: "vulnerability"
aliases: ["CVE-2026-117937"]
title: "Firefox: invalid pointer in JavaScript engine fixed in version 159"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browser", "desktop", "firefox", "runtime"]
not_affected_if: ["fixed-version"]
published_at: "2026-10-27T14:16:49+00:00"
first_seen_at: "2026-10-27T14:32:23+00:00"
updated_at: "2026-10-27T14:36:58+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117937", "first_seen_at": "2026-10-27T14:32:23+00:00"}]
---

# Firefox: invalid pointer in JavaScript engine fixed in version 159

Firefox's JavaScript engine mishandles a pointer, which is a memory-safety bug. The sources do not say what an attacker can achieve with it, and the description gives no severity.

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

## How to check

- Check the installed Firefox version in the About Firefox dialog or with `firefox --version`; versions below `159`, `115.44` (ESR), or `153.6` (ESR) are affected.

## Fix

- Update Firefox to `159` or later, or to ESR `115.44` or `153.6`.

## Timeline

- 2026-10-27T14:32:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117937

## From the sources

Invalid pointer in the JavaScript Engine component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

---

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