Apple macOS Improper Authentication Vulnerability
Apple — macOS
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.
9.8
9.9%
Vector breakdown
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- Aug 6, 2026
- Modified
- Oct 26, 2026
- Added to KEV
- Aug 18, 2026
- Federal patch due
- Aug 21, 2026
CISA required action
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.
Weakness classification
Affected packages
Proof-of-concept & exploitation references
Weaponization
Public repositories whose name or description references CVE-2026-65400, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit — cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
No public GitHub repositories referencing CVE-2026-65400 were found at last check. Absence here is not proof no exploit exists — see the references below for vendor advisories and write-ups.
References
Frequently asked questions
What is CVE-2026-65400?
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.
How severe is CVE-2026-65400?
CVE-2026-65400 has a CVSS base score of 9.8 out of 10 (CVSS 3.1).
Is CVE-2026-65400 actively exploited in the wild?
Yes. CVE-2026-65400 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Aug 18, 2026, meaning CISA has confirmed evidence of active exploitation.
What is the EPSS score for CVE-2026-65400?
9.9% - meaning FIRST.org's EPSS model estimates a 9.9% probability this vulnerability will be exploited in the wild within 30 days (95% percentile among all scored CVEs).
What type of vulnerability is CVE-2026-65400?
CVE-2026-65400 is classified under CWE-287 (CWE-287 Improper Authentication).
Cross-checked against
Impactr finds and proves whether CVE-2026-65400 — or flaws like it — are actually reachable in your own web apps and APIs, with a reproducible exploit as evidence.