What is CVE-2026-58299?

CVE-2026-58299 is a high-severity vulnerability in Microsoft Edge (Chromium-based), classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 7.5/10. Published 2026-07-03.

How severe is CVE-2026-58299?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Microsoft Edge (Chromium-based)

CVE-2026-58299

Time-of-check time-of-use (toctou) race condition in Microsoft Edge for Android allows an unauthorized attacker to execute code over a network.

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Microsoft Edge (Chromium-based) — versions 1.0.0.0

Weakness classification (CWE)

CWE-367 — Time-of-check Time-of-use (TOCTOU) Race Condition

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-58299?: CVE-2026-58299 is a high-severity vulnerability in Microsoft Edge (Chromium-based), classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 7.5/10. Published 2026-07-03.
How severe is CVE-2026-58299?: High severity. CVSS v3 base score is 7.5 out of 10.