{"id":"CVE-2026-84009","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-84009","generatedAt":"2026-10-27T23:57:08.690Z","title":"Time-of-check time-of-use (toctou) race condition in Windows Projected File System allows an authorized attacker to perform tampering locally.","description":"Time-of-check time-of-use (toctou) race condition in Windows Projected File System allows an authorized attacker to perform tampering locally.","published":"2026-10-13T19:20:51.000Z","lastModified":"2026-10-19T19:16:11.000Z","status":"Analyzed","sourceIdentifier":"secure@microsoft.com","cvss":{"version":"3.1","score":4.7,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N"},"cwe":["CWE-367"],"affected":["microsoft/windows 10 1809","microsoft/windows 10 21h2","microsoft/windows 10 22h2","microsoft/windows 11 23h2","microsoft/windows 11 24h2","microsoft/windows 11 25h2","microsoft/windows 11 26h1","microsoft/windows 11 26h2","microsoft/windows server 2019","microsoft/windows server 2022","microsoft/windows server 2025"],"epss":{"score":0.00197,"percentile":0.0931,"date":"2026-10-26","history":[{"date":"2026-10-14","score":0.00202,"percentile":0.09389}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-13T19:20:51.000Z","detail":{"score":"4.7","severity":"MEDIUM","publishedAt":"2026-10-13T19:20:50.927Z"},"summary":"New CVE, medium severity (CVSS 4.7)."}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-84009","tags":["Vendor Advisory","Patch"],"source":"secure@microsoft.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-84009","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}