Intel

CVE-2026-66321

edge_chromium: Access of Resource Using Incompatible Type ('Type Confusion') (CVE-2026-66321)

criticalEPSS 1.1%

Affected

  • microsoft/edge_chromium lt *..151.0.4129.59

Description

Access of resource using incompatible type ('type confusion') in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.

Source: NVD (NIST)CVE.org (MITRE)cvelistv5Microsoft Security Update GuideBSI CSAFBSI WID Portal

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

microsoftedge_chromium
151.0.4129.59fixed from 151.0.4129.59

Metrics

XIEM Effective CVSS
9.6
Source: nvd-v3
EPSS percentile
63.7 %
High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
—
Show all metrics
Severity
critical
Priority score
93.63
Exploit maturity
no public PoC known
CVSS v3
7.4
EPSS score
1.1 %
Moderate — model estimates 1-10% exploitation likelihood.
Published
2026-08-04 00:17 UTC
CWE
CWE-843

Weakness classes (CWE)

  • CWE-843Base

    Access of Resource Using Incompatible Type ('Type Confusion')

    The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

    cwe.mitre.org →

References & sources

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. CVE Modified2026-08-04 15:16 UTC· 134c704f-9b21-4f2e-91b3-4a467353bcc0
    • SSVC: {"id":"CVE-2026-66321","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalI…
  2. New CVE Received2026-08-04 00:17 UTC· secure@microsoft.com
    • Affected: Microsoft Edge (Chromium-based)
    • Description: Access of resource using incompatible type ('type confusion') in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.
    • CVSS V3.1: AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
    • CWE: CWE-843

Linked advisories