CVE-2026-65400

Apple macOS: Improper Authentication

As of , CVE-2026-65400 in Apple macOS is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch now.

Exploited
Yes: CISA listed it on 18 August 2026
US federal deadline
21 August 20263 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
Forensic triage
Required by CISA under BOD 26-04Agencies must also look for signs that attackers already got in.
EPSS score
0.02Higher than 76% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
Vendor advice: support.apple.comLinks below, from CISA's entry.

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.

CISA's required action

What the flaw is

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

CISA's description

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.

The CVE record's description, from apple

CVE published
6 August 2026
Assigned by
apple
CVSS
9.8 Critical (CVSS 3.1, from CISA-ADP)
CWE-287
Improper Authentication
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

macOS: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2021-30657UnspecifiedApple macOSPatch this weekMetasploit module; EPSS 0.690.69
CVE-2022-22675Out-of-Bounds WriteApple macOSPatch soon0.12
CVE-2021-30713UnspecifiedApple macOSPatch soon0.07
CVE-2022-22674Out-of-Bounds ReadApple macOSPatch soon0.01
CVE-2019-8526Use-After-FreeApple macOSPatch soon0.01

Read further