CVE-2026-65400: Apple macOS Improper Authentication Vulnerability

CISA Known Exploited Vulnerability (KEV)

Description

Apple macOS contains an improper authentication vulnerability that could allow an attacker on the network to authenticate to Screen Sharing without valid credentials.

Required action (CISA)

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.

Notes

https://support.apple.com/en-us/148170; https://support.apple.com/en-us/148171; https://support.apple.com/en-us/148172 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-65400

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-65400
• KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog