What is CVE-2026-91712?

CVE-2026-91712 is a high-severity vulnerability in Google Chrome, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 8.3/10. Published 2026-09-15.

How severe is CVE-2026-91712?

High severity. CVSS v3 base score is 8.3 out of 10.

Vulnerability in Google Chrome

CVE-2026-91712

Race condition in Extensions in Google Chrome on on Mac prior to 153.0.8010.47 allowed a remote attacker who had compromised the renderer process to potentially execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: High)

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

Published 2026-09-15 · last modified 2026-09-17.

CVSS v3 metric

CVSS v3 base score 8.3 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (19.0th percentile), scored 2026-10-31.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 19.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Google Chrome

Weakness classification (CWE)

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

References

chromereleases.googleblog.com/2026/09/stable-channel-update-for-desktop_0541751… (Release Notes, Vendor Advisory)
issues.chromium.org/issues/521486621 (Permissions Required)

Frequently asked questions

What is CVE-2026-91712?: CVE-2026-91712 is a high-severity vulnerability in Google Chrome, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 8.3/10. Published 2026-09-15.
How severe is CVE-2026-91712?: High severity. CVSS v3 base score is 8.3 out of 10.