FalehSec Exploited-vulnerability triage · joined from CISA KEV, NVD CVSS and EPSS

CVE-2026-65400

Apple · macOS · Apple macOS Improper Authentication Vulnerability

Verdict
Patch soon · actively exploited, reachable from the internet without credentials, and in the top half of CVEs by near-term exploitation probability

Added to CISA KEV 2026-08-18 · exploited in the wild for 40 days

What an attacker can reach How likely Time What CISA says to do Sources All 545

What an attacker can reach

CVSS 9.8 CRITICAL. The score is a summary; these three components are the part that decides whether something scanning the internet can use it.

Attack vectornetworkreachable over the network, with no local access needed
Privileges requirednoneneeds no credentials at all
User interactionnonecan be triggered with nobody interacting with the page or request
Base vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
WeaknessCWE-287

This describes the vulnerability. It says nothing about whether your systems run it.

How likely

EPSS puts the probability of exploitation in the next 30 days at 0.0122, which places it in the top half of all tracked CVEs. The percentile is the more useful half: 0.18 in absolute terms sounds low until you know most of the internet-facing software in the world scores under that.

EPSS probability0.0122
Percentile0.674 — top half

Time

Added to KEV2026-08-18
Days exploited40
Federal remediation duenot set
Ransomware useno known ransomware campaign use

What CISA says to do

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, macOS Tahoe 26.7. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.

Sources