What is CVE-2026-8520?

CVE-2026-8520 is a high-severity vulnerability in Apple macOS, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.3/10. Published 2026-05-14.

How severe is CVE-2026-8520?

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

Vulnerability in Apple macOS

CVE-2026-8520

Race in Payments in Google Chrome prior to 148.0.7778.168 allowed a remote attacker to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Critical)

Vulnerability class: Race Condition

Published 2026-05-14 · last modified 2026-06-17.

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: 0.002 (12.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.001

Affected products

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_12.html (Product, Vendor Advisory)
issues.chromium.org/issues/503619813 (Permissions Required)

Frequently asked questions

What is CVE-2026-8520?: CVE-2026-8520 is a high-severity vulnerability in Apple macOS, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.3/10. Published 2026-05-14.
How severe is CVE-2026-8520?: High severity. CVSS v3 base score is 8.3 out of 10.