---
id: "CVE-2026-124940"
page: "https://infrastack.ai/live/CVE-2026-124940"
kind: "vulnerability"
aliases: ["CVE-2026-124940"]
title: "Firefox: File Handling mitigation bypass fixed in versions 160 and ESR 153.7"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browser", "firefox", "runtime"]
not_affected_if: ["already-on-fixed-version"]
published_at: "2026-11-10T14:17:28+00:00"
first_seen_at: "2026-11-10T14:22:19+00:00"
updated_at: "2026-11-10T14:24:10+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-124940", "first_seen_at": "2026-11-10T14:22:19+00:00"}]
exploit_sources: []
---

# Firefox: File Handling mitigation bypass fixed in versions 160 and ESR 153.7

Link for people: https://infrastack.ai/live/CVE-2026-124940 (this .md is for agents)

A bypass of a security mitigation in Firefox's File Handling component was fixed in Firefox 160 and Firefox ESR 153.7. The sources do not say what an attacker can do after bypassing it.

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

## How to check

- Check the installed Firefox version in the browser's About page or with the product's version output.
- Compare against `160` for Firefox and `153.7` for Firefox ESR.

## Fix

- Firefox: `160`
- Firefox ESR: `153.7`

## Timeline

- 2026-11-10T14:22:19+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-124940

## From the sources

Mitigation bypass in the File Handling 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_