---
id: "CVE-2026-124927"
page: "https://infrastack.ai/live/CVE-2026-124927"
kind: "vulnerability"
aliases: ["CVE-2026-124927"]
title: "Firefox: WebRender graphics flaw breaks site isolation, fixed in 160"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["browsers", "firefox", "other"]
not_affected_if: ["firefox-160-or-later", "firefox-esr-153.7-or-later"]
published_at: "2026-11-10T14:17:26+00:00"
first_seen_at: "2026-11-10T14:22:18+00:00"
updated_at: "2026-11-10T14:24:21+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-124927", "first_seen_at": "2026-11-10T14:22:18+00:00"}]
exploit_sources: []
---

# Firefox: WebRender graphics flaw breaks site isolation, fixed in 160

Link for people: https://infrastack.ai/live/CVE-2026-124927 (this .md is for agents)

A site isolation flaw in Firefox's WebRender graphics component can let content from one website cross into another site's context. The sources do not describe the exact attacker capability beyond this.

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

## How to check

- Check the Firefox version with `about:support` or the Help menu; the sources name Firefox 160 and Firefox ESR 153.7 as fixed.
- Confirm the ESR channel in use if the browser is on Extended Support Release.

## Fix

- Firefox: `160` or later
- Firefox ESR: `153.7` or later

## Timeline

- 2026-11-10T14:22:18+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-124927

## From the sources

Site isolation issue in the Graphics: WebRender component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_