Vulnerability · CVE-2026-65400
Apple macOS Improper Authentication Vulnerability
Published Aug 6, 2026 · catalog updated Sep 15, 2026 · Apple MacOS X
Patch now
CVE-2026-65400 is in the CISA known-exploited catalog, due Aug 21, 2026. Confirm Apple MacOS X against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- Critical9.8
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 1.72%
- Remediation
- Remediation guidance
- Affected products
- cpe apple/macos · vendor Apple MacOS X · vendor 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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe apple/macosversion unspecified
- vendor Apple MacOS Xversion unspecified
- vendor Apple macOSversion unspecified
How to fix CVE-2026-65400
Recommended remediation
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 due date Aug 21, 2026.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2026-65400 is in the CISA known-exploited catalog, due Aug 21, 2026. Confirm Apple MacOS X against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. 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.
What should an analyst verify?
CWE-287: Improper Authentication. EPSS 1.72%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Aug 6, 2026 · Catalog
Detected
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.
Aug 18, 2026 · CISA KEV
Known exploited
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
Aug 21, 2026 · CISA KEV
Remediation due
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
Sep 15, 2026 · Catalog
Updated
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
- CISA KEVConfirmed exploitationCVE-2026-65400
Apple macOS contains an improper authentication vulnerability that could allow an attacker on the network to authenticate to Screen Sharing without valid credentials.
cisa.gov - CVE.orgVulnerability recordCVE-2026-65400
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-65400
30-day exploitation probability 1.7%
first.org - NIST NVDVulnerability recordCVE-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 val
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2026-65400
Apple macOS contains an improper authentication vulnerability that could allow an attacker on the network to authenticate to Screen Sharing without valid credentials.
vulncheck.com
References
- Mailing List · seclists.org
- Broken Link · seclists.org
- Third Party Advisory · advisories.ncsc.nl
- CISA note · nvd.nist.gov
- VulnCheck exploitation evidence · previdian.com
- VulnCheck exploitation evidence · research.checkpoint.com
- CISA note · support.apple.com
- CISA note · support.apple.com
- CISA note · support.apple.com
- Release Notes · support.apple.com
- Release Notes · support.apple.com
- CISA note · cisa.gov
- CISA note · cisa.gov
- VulnCheck exploitation evidence · cisa.gov
- VulnCheck exploitation evidence · iru.com
- VulnCheck exploitation evidence · ncsc.nl
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.