{"id":"CVE-2020-1154","title":"An elevation of privilege vulnerability exists when the Windows Common Log File System (CLFS) driver improperly handles objects in memory","summary":"An elevation of privilege vulnerability exists when the Windows Common Log File System (CLFS) driver improperly handles objects in memory. An attacker who successfully exploited this vulnerability could run processes in an elevated conte…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","vendor":"microsoft","product":"windows_10","affected":["windows_10","windows_10 = 1607","windows_10 = 1709","windows_10 = 1803","windows_10 = 1809","windows_10 = 1903","windows_10 = 1909","windows_7","windows_8.1","windows_rt_8.1","windows_server_2008","windows_server_2008 = r2","windows_server_2012","windows_server_2012 = r2","windows_server_2016","windows_server_2016 = 1803","windows_server_2016 = 1903","windows_server_2016 = 1909","windows_server_2019"],"published":"2020-05-21","updated":"2026-08-19","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2020-1154","references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1154","label":"secure@microsoft.com"},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1154","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.00944,"epssPercentile":0.59552,"ingestedAt":"2026-08-19T17:42:39.660Z","slug":"CVE-2020-1154","body":"## Overview\n\nAn elevation of privilege vulnerability exists when the Windows Common Log File System (CLFS) driver improperly handles objects in memory. An attacker who successfully exploited this vulnerability could run processes in an elevated context.\nTo exploit the vulnerability, an attacker would first have to log on to the system, and then run a specially crafted application to take control over the affected system.\nThe security update addresses the vulnerability by correcting how CLFS handles objects in memory.\n\n## Affected\n\n- `windows_10`\n- `windows_10 = 1607`\n- `windows_10 = 1709`\n- `windows_10 = 1803`\n- `windows_10 = 1809`\n- `windows_10 = 1903`\n- `windows_10 = 1909`\n- `windows_7`\n- `windows_8.1`\n- `windows_rt_8.1`\n- `windows_server_2008`\n- `windows_server_2008 = r2`\n- `windows_server_2012`\n- `windows_server_2012 = r2`\n- `windows_server_2016`\n- `windows_server_2016 = 1803`\n- `windows_server_2016 = 1903`\n- `windows_server_2016 = 1909`\n- `windows_server_2019`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}