---
id: "CVE-2026-117969"
kind: "vulnerability"
aliases: ["CVE-2026-117969"]
title: "Firefox: JavaScript JIT invalid pointer may allow memory corruption"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browsers", "desktop", "firefox", "runtime"]
not_affected_if: ["already-on-fixed-version"]
published_at: "2026-10-27T14:16:54+00:00"
first_seen_at: "2026-10-27T14:32:24+00:00"
updated_at: "2026-10-27T14:35:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117969", "first_seen_at": "2026-10-27T14:32:24+00:00"}]
---

# Firefox: JavaScript JIT invalid pointer may allow memory corruption

Firefox's JavaScript engine JIT compiler handles a pointer incorrectly. The sources do not describe what an attacker can achieve beyond that, but memory corruption in a JIT typically risks code execution in the browser.

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

## How to check

- Check the installed Firefox version via Help > About Firefox, or `firefox --version`.
- Check whether the ESR channel is in use, with ESR builds at `153.6` or later being patched.

## Fix

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

## Timeline

- 2026-10-27T14:32:24+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117969

## From the sources

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

---

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