Improper authentication in macOS - CVE-2026-65400

 

Improper authentication in macOS - CVE-2026-65400

Published: August 17, 2026


Vulnerability identifier: #VU143639
CSH Severity: High
CVSS v4: 8.6 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-65400
CWE-ID: CWE-287
Exploitation vector: Adjecent network
Exploit availability: The vulnerability is being exploited in the wild

Vulnerability details

The vulnerability allows a remote attacker to bypass authentication.

The vulnerability exists due to improper authentication in Screen Sharing when handling network authentication attempts. A remote attacker can send crafted authentication requests to bypass authentication.


Affected software

macOS

How to mitigate CVE-2026-65400

Install security update from vendor's website.

macOS - addressed in versions 26.6.1 25G76, 14.8.9 23J631, 15.7.9 24G830

External References

Related Security Bulletins