CVE-2026-20639highCWE-190

CVE-2026-20639: high-severity vulnerability in Apple macOS

Published 25 Mar 2026 · Updated 02 Apr 2026

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.6%

An integer overflow was addressed with improved input validation. This issue is fixed in macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.3. Processing a maliciously crafted string may lead to heap corruption.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Apple · macOS

Related CVEs — Apple macOS

In the same product, most dangerous first.

CVE-2021-30860HIGHCVE-2021-30860EPSS 76.0%KEV CVE-2021-30657MEDIUMCVE-2021-30657EPSS 68.5%KEV CVE-2025-43300CRITICALCVE-2025-43300EPSS 65.2%KEV CVE-2023-41064HIGHCVE-2023-41064EPSS 53.4%KEV CVE-2023-32434HIGHCVE-2023-32434EPSS 51.5%KEV CVE-2021-30807HIGHCVE-2021-30807EPSS 28.8%KEV

References

https://support.apple.com/en-us/126348 https://support.apple.com/en-us/126795 https://support.apple.com/en-us/126796