CVE-2026-66314

Microsoft Edge (Chromium-based) Information Disclosure Vulnerability

Published Aug 3, 2026 CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed
Description
Time-of-check time-of-use (toctou) race condition in Microsoft Edge (Chromium-based) allows an unauthorized attacker to disclose information over a network.

Analysis

AI-generated

Technical impact

The vulnerability is a time‑of‑check time‑of‑use race condition in Microsoft Edge (Chromium‑based). It allows an unauthorized attacker to read sensitive data that is otherwise protected. The flaw can lead to the disclosure of confidential information over a network, potentially compromising the privacy of users and the confidentiality of data managed by the browser.

Affected Systems

Affected systems are all deployments of Microsoft Edge (Chromium‑based). No specific version range is provided; therefore every installed copy of that browser may be vulnerable until a patch is applied.

Risk and Exploitability

The CVSS score of 6.5 indicates moderate severity. No EPSS score is available, and the vulnerability is not listed in the CISA KEV catalog. The attack vector is inferred to be remote over a network, as the description states an unauthorized attacker can disclose information over a network. Exploitation would require the attacker to trigger the race condition, which could involve sending specially crafted requests to the browser or manipulating its internal state.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the latest Microsoft Edge (Chromium‑based) security update when it becomes available.
  • Limit network access to the Edge browser by configuring firewall rules or disabling remote features that may expose the browser.
  • Monitor network traffic and logs for unexpected data exfiltration or abnormal interactions involving Microsoft Edge.

Generated by OpenCVE AI on August 4, 2026 at 09:32 UTC.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Time-of-check time-of-use (toctou) race condition in Microsoft Edge (Chromium-based) allows an unauthorized attacker to disclose information over a network.
Title Microsoft Edge (Chromium-based) Information Disclosure Vulnerability
First Time appeared Microsoft
Microsoft edge Chromium
Weaknesses CWE-367
CPEs cpe:2.3:a:microsoft:edge_chromium:*:*:*:*:*:*:*:*
Vendors & Products Microsoft
Microsoft edge Chromium
References
Metrics cvssV3_1

{'score': 6.5, 'vector': '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'}

Weaknesses
  • CWE-367

    Time-of-check Time-of-use (TOCTOU) Race Condition

Sources

Status
PUBLISHED
Assigner
microsoft
Published
Updated
Nov 10, 2026, 10:36 PM
Reserved
Jul 24, 2026, 6:06 PM
Status
Analyzed
Published
Aug 4, 2026, 12:17 AM
Modified
Oct 23, 2026, 11:10 PM