Apple macOS Improper Authentication Vulnerability
Apple · macOS
The flaw is an improper authentication weakness in Apple's macOS, specifically in the Screen Sharing component, which was addressed through improved state management. An attacker on the network can potentially authenticate to Screen Sharing without valid credentials, requiring no privileges or user interaction.
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.
- Exploited
- Yes, in CISA KEV
- Reports
- 0
- Tactics
- 3/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 1 day after disclosure. Public exploit code (PoC-in-GitHub) appeared 12 days after disclosure.
- Disclosedday 0
- First seen exploitedVulnCheck KEV evidence+1 day
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
2 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order, 2 cited passages 2Initial AccessTA0001
Remote service authentication bypass via Screen Sharing
An attacker on the network may be able to authenticate to Screen Sharing without valid credentials
Lateral MovementTA0008
Remote access gained through Screen Sharing service
An attacker on the network may be able to authenticate to Screen Sharing without valid credentials
Detection
0 rules for this CVE · 31 general rules for its techniquesRules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2026-65400 directly.CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
External Remote ServicesT113320 general rules
- External Remote SMB Logon from Public IPhightest
- OpenCanary - SSH Login Attempthightest
- OpenCanary - SSH New Connection Attempthightest
- OpenCanary - Telnet Login Attempthightest
- Running Chrome VPN Extensions via the Registry 2 VPN Extensionhightest
- Unusual Child Process of dns.exehightest
- Unusual File Deletion by Dns.exehightest
- Unusual File Modification by dns.exehightest
Remote ServicesT102111 general rules
- New RDP Connection Initiated From Domain Controllerhightest
- OpenCanary - FTP Login Attempthightest
- OpenCanary - SMB File Open Requesthightest
- OpenCanary - SNMP OID Requesthightest
- OpenCanary - SSH Login Attempthightest
- OpenCanary - SSH New Connection Attempthightest
- OpenCanary - VNC Connection Attempthightest
- Privilege Escalation via Named Pipe Impersonationhightest
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Not named in any threat report yetAlso mentioned in 36 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 31, 202630 Oct 2026
- Actively_Exploited_Kev | Oct 30, 202629 Oct 2026
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- 30 more on OTX