Apple macOS Improper Authentication Vulnerability
An authentication issue was addressed with improved state management. This issue is fixed in macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
What happened
An authentication issue was addressed with improved state management. This issue is fixed in macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
CISA lists it as exploited, added 18 Aug 2026.
Does it affect you
Names Apple macOS. Enter the product and version you run to place it against the affected range the vendor published.
What to do
- Follow the vendor advisory for the fixed release and any interim mitigation.
support.apple.com - Follow the vendor advisory for the fixed release and any interim mitigation.
support.apple.com - Follow the vendor advisory for the fixed release and any interim mitigation.
support.apple.com - 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.
cisa.gov
CISA’s notes for this entry:
- support.apple.com/en-us/148170
- support.apple.com/en-us/148171
- support.apple.com/en-us/148172
- BOD 26-04: cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- Forensics Triage Requirements: cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- nvd.nist.gov/vuln/detail/CVE-2026-65400
Affected, as published to NVD
- macos
- Apple macOS: 14.0 up to the fix in 14.8.9
The record
- NVD status
- Analyzed
- Published
- 06 Aug 2026, last modified 19 Aug 2026 (NVD)
- Severity
- CVSS 3.1 base score 9.8, Critical — computed here from the vector; NVD states 9.8.
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weakness
- CWE-287 Improper Authentication (NVD; names by MITRE)
- Exploitation
- Listed in CISA’s Known Exploited Vulnerabilities catalogue since 18 Aug 2026; federal remediation due 21 Aug 2026. CISA entry
- Exploit probability
- EPSS 9.9%, 95th percentile — FIRST. FIRST EPSS
- Vendor
- Apple · macOS (CISA)
References on the NVD record
- support.apple.com/en-us/148170Release NotesVendor Advisory
- support.apple.com/en-us/148171Release NotesVendor Advisory
- support.apple.com/en-us/148172Release NotesVendor Advisory
- advisories.ncsc.nl/2026/ncsc-2026-0280.htmlThird Party Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-65400US Government Resource
- seclists.org/fulldisclosure/2026/Aug/36Mailing List
- seclists.org/fulldisclosure/2026/Aug/37Broken Link
Reporting that names this identifier
- Critical macOS, SharePoint, vCenter, and Microsoft IKE Flaws Under Active Exploitation — The Hacker News, 16 d ago
- CISA Adds Four Known Exploited Vulnerabilities to Catalog — CISA, 17 d ago
- Apple macOS Screen Sharing Flaw Exploited on Internet-Exposed Macs to Install Monero Miner — The Hacker News, 20 d ago
Sources
The verdict above is computed from the products and versions you entered and the affected ranges the vendor published to NVD. It does not inspect your environment, and this site never reports a product as unaffected: why.