{"id":"CVE-2026-41091","aliases":["EUVD-2026-31101","GHSA-h776-j9jw-992p"],"status":"published","title":"Microsoft Defender Elevation of Privilege Vulnerability","description":"Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.","severity":{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.08202,"percentile":0.94955,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-59"],"published":"2026-05-20T13:09:13Z","modified":"2026-08-10T15:13:49Z","kev":{"date_added":"2026-05-20","due_date":"2026-06-03","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Unknown"},"exploitation":[{"source":"euvd","since":"2026-05-20"},{"source":"kev","since":"2026-05-20"}],"exploits":[{"source":"pocgithub","id":"ashrafzaryouh/CVE-2026-41091","title":"ashrafzaryouh/CVE-2026-41091","date":"2026-05-21","url":"https://github.com/ashrafzaryouh/CVE-2026-41091"},{"source":"pocgithub","id":"ridhinva/defender-privilege-escalation-scanner","title":"ridhinva/defender-privilege-escalation-scanner","date":"2026-05-22","url":"https://github.com/ridhinva/defender-privilege-escalation-scanner"},{"source":"pocgithub","id":"tc4dy/CVE-2026-41091-PoC-Exploit","title":"tc4dy/CVE-2026-41091-PoC-Exploit","date":"2026-06-20","url":"https://github.com/tc4dy/CVE-2026-41091-PoC-Exploit"},{"source":"pocgithub","id":"s4m98/RedSun-","title":"s4m98/RedSun-","date":"2026-08-09","url":"https://github.com/s4m98/RedSun-"}],"products":[{"vendor":"microsoft","product":"defender"},{"vendor":"microsoft","product":"malware_protection_engine"},{"vendor":"microsoft","product":"microsoft malware protection engine"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-41091","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-41091","tags":["government-resource","Third Party Advisory","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-41091"},{"url":"https://github.com/advisories/GHSA-h776-j9jw-992p"}],"sources":{"cve":[{"id":"CVE-2026-41091","title":"Microsoft Defender Elevation of Privilege Vulnerability","description":"Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges 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('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-05-20T15:35:31Z","modified":"2026-05-20T18:31:35Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T15:08:13.87243Z"}],"kev":[{"id":"CVE-2026-41091","title":"Microsoft Defender Link Following Vulnerability","description":"Microsoft Defender contains a link following vulnerability that allows an authorized attacker to elevate privileges locally.","cwes":["CWE-59"],"kev":{"date_added":"2026-05-20","due_date":"2026-06-03","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Unknown"},"updated_at":"2026-11-02T17:00:15.999436Z"}],"nvd":[{"id":"CVE-2026-41091","description":"Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-05-20T13:16:29.173Z","modified":"2026-07-24T10:10:00.197Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T14:12:19.752984Z"}]}}