{"id":"CVE-2019-1040","url":"https://www.cyber-defence.io/tools/cve/CVE-2019-1040","generatedAt":"2026-10-28T21:27:17.171Z","title":"A tampering vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLM MIC (Message Integrity Check) protection.","description":"A tampering vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLM MIC (Message Integrity Check) protection. An attacker who successfully exploited this vulnerability could gain the ability to downgrade NTLM security features.\nTo exploit this vulnerability, the attacker would need to tamper with the NTLM exchange. The attacker could then modify flags of the NTLM packet without invalidating the signature.\nThe update addresses the vulnerability by hardening NTLM MIC protection on the server-side.","published":"2019-06-12T14:29:04.000Z","lastModified":"2026-06-17T02:27:40.000Z","status":"Modified","sourceIdentifier":"secure@microsoft.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N"},"cwe":[],"affected":["microsoft/windows 10","microsoft/windows 7","microsoft/windows 8.1","microsoft/windows rt 8.1","microsoft/windows server 2008","microsoft/windows server 2012","microsoft/windows server 2016","microsoft/windows server 2019"],"epss":{"score":0.48043,"percentile":0.98849,"date":"2026-10-27","history":[{"date":"2026-09-21","score":0.33303,"percentile":0.98338},{"date":"2026-09-22","score":0.48043,"percentile":0.988}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 48.0%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[{"kind":"epss","label":"EPSS jump","at":"2026-09-22T00:00:00.000Z","detail":{"to":0.48043,"from":0.33303,"percentile":0.988},"summary":"EPSS moved from 33.3% to 48.0% probability of exploitation in the next thirty days."}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1040","source":"secure@microsoft.com"},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1040","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2019-1040","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."}