{"id":"CVE-2026-65400","published":"2026-08-06T22:18:14Z","modified":"2026-10-24T16:10:00Z","title":"Apple macOS Improper Authentication Vulnerability","vendor":"Apple","product":"macOS","tier":"core","eol":null,"description":{"text":"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.","provenance":"source","from":"NVD"},"summary":{"text":"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.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:14:20Z"},"cvss":{"score":9.8,"severity":"CRITICAL","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.01723,"percentile":0.77487,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2026-08-18","dueDate":"2026-08-21","ransomware":false,"requiredAction":"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","provenance":"source"},"vulncheckKev":{"dateAdded":"2026-08-07","exploitedFirstSeen":"2026-08-07","ransomware":false,"evidence":[{"url":"https://www.ncsc.nl/alerts/kwetsbaarheid-in-macos-screen-sharing","date":"2026-08-07"},{"url":"https://advisories.ncsc.nl/2026/ncsc-2026-0280.html","date":"2026-08-12"},{"url":"https://previdian.com/CVE-2026-65400","date":"2026-08-15"},{"url":"https://research.checkpoint.com/2026/17th-august-threat-intelligence-report/","date":"2026-08-17"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2026-08-18"},{"url":"https://www.iru.com/blog/inside-the-screensharingd-bugs-how-macos-screen-sharing-went-from-root-file-access-to-pre-auth-compromise","date":"2026-09-01"},{"url":"https://cert.europa.eu/publications/threat-intelligence/cb26-09/","date":"2026-09-03"},{"url":"https://www.recordedfuture.com/blog/august-2026-cve-landscape","date":"2026-09-08"}],"evidenceTotal":8,"provenance":"source"},"exploited":true,"otx":{"pulseCount":36,"pulses":[{"name":"Actively_Exploited_Kev | Oct 31, 2026","url":"https://otx.alienvault.com/pulse/6ae4aefab0c2191cecd41862","created":"2026-10-30"},{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"}],"provenance":"machine"},"cwes":[{"id":"CWE-287","name":"Improper Authentication"}],"references":[{"url":"https://support.apple.com/en-us/148170","tags":["Release Notes","Vendor Advisory"]},{"url":"https://support.apple.com/en-us/148171","tags":["Release Notes","Vendor Advisory"]},{"url":"https://support.apple.com/en-us/148172","tags":["Release Notes","Vendor Advisory"]},{"url":"https://support.apple.com/en-us/149035","tags":["Release Notes","Vendor Advisory"]},{"url":"https://support.apple.com/en-us/149042","tags":["Release Notes","Vendor Advisory"]},{"url":"http://seclists.org/fulldisclosure/2026/Aug/36","tags":["Mailing List"]},{"url":"http://seclists.org/fulldisclosure/2026/Aug/37","tags":["Broken Link"]},{"url":"https://advisories.ncsc.nl/2026/ncsc-2026-0280.html","tags":["Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-65400","tags":["US Government Resource"]}],"techniques":[{"id":"T1133","name":"External Remote Services","tactics":["initial-access","persistence"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Remote service authentication bypass via Screen Sharing","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"An attacker on the network may be able to authenticate to Screen Sharing without valid credentials","start":196,"end":294}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1021","name":"Remote Services","tactics":["lateral-movement"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Remote access gained through Screen Sharing service","mappingType":"primary_impact","evidence":[{"from":"description","quote":"An attacker on the network may be able to authenticate to Screen Sharing without valid credentials","start":196,"end":294}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2026-54216","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-54216","exploited":true,"exploitedSince":"2026-08-18","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":3,"skipped":0,"earliest":"2026-08-18","earliestUrl":"https://github.com/HORKimhab/CVE-2026-65400","repos":[{"name":"panchocosil/CVE-2026-65400-poc","url":"https://github.com/panchocosil/CVE-2026-65400-poc","stars":10,"created":"2026-08-21"},{"name":"acheong08/CVE-2026-65400","url":"https://github.com/acheong08/CVE-2026-65400","stars":10,"created":"2026-08-22"},{"name":"HORKimhab/CVE-2026-65400","url":"https://github.com/HORKimhab/CVE-2026-65400","stars":3,"created":"2026-08-18"}]},"first":{"date":"2026-08-18","source":"PoC-in-GitHub","url":"https://github.com/HORKimhab/CVE-2026-65400"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1133"],"provenance":"ai"},{"stage":"primary","techniques":["T1021"],"provenance":"ai"}],"timeline":[{"date":"2026-08-06","kind":"published","label":"Published 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