---
id: CVE-2026-66314
title: Microsoft Edge (Chromium-based) Information Disclosure Vulnerability
summary: >-
  Time-of-check time-of-use (toctou) race condition in Microsoft Edge
  (Chromium-based) allows an unauthorized attacker to disclose information over
  a network.
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C'
cvssSource: cna
cwe:
  - CWE-367
vendor: Microsoft
product: Microsoft Edge (Chromium-based)
affected:
  - edge_chromium-based >= 1.0.0.0 < 151.0.4129.59
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-08-05T14:29:00.845434Z'
published: '2026-08-03'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T18:21:00.450Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-66314'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66314'
    label: Microsoft Edge (Chromium-based) Information Disclosure Vulnerability
tags:
  - cve.org
epss: 0.00574
epssPercentile: 0.45022
ingestedAt: '2026-09-08T17:06:31.926Z'
---

## Overview

Time-of-check time-of-use (toctou) race condition in Microsoft Edge (Chromium-based) allows an unauthorized attacker to disclose information over a network.

## Affected

- `edge_chromium-based >= 1.0.0.0 < 151.0.4129.59`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.