{"id":"CVE-2021-33771","published":"2021-07-14T18:15:10Z","modified":"2026-08-10T19:58:46Z","title":"Microsoft Windows Kernel Privilege Escalation Vulnerability","vendor":"Microsoft","product":"Windows","tier":"core","eol":null,"description":{"text":"Windows Kernel Elevation of Privilege Vulnerability","provenance":"source","from":"NVD"},"summary":{"text":"A memory-buffer bounds flaw in the Windows kernel allows an attacker to elevate privileges on affected Windows systems. 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instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-33771","provenance":"source"},"vulncheckKev":{"dateAdded":"2021-07-13","exploitedFirstSeen":"2021-07-13","ransomware":false,"evidence":[{"url":"https://api.msrc.microsoft.com/cvrf/v3.0/cvrf/2021-Jul","date":"2021-07-13"},{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2021-07-13"},{"url":"https://citizenlab.ca/2021/07/hooking-candiru-another-mercenary-spyware-vendor-comes-into-focus/","date":"2021-07-15"},{"url":"https://www.microsoft.com/security/blog/2021/07/15/protecting-customers-from-a-private-sector-offensive-actor-using-0-day-exploits-and-devilstongue-malware/","date":"2021-07-15"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2021-11-03"},{"url":"https://storage.googleapis.com/gweb-uniblog-publish-prod/documents/Buying_Spying_-_Insights_into_Commercial_Surveillance_Vendors.pdf","date":"2024-02-06"},{"url":"https://falconfeeds.io/blogs/the-politics-of-patch-delays-when-vulnerability-disclosure-collides-with-national-interests","date":"2026-01-29"}],"evidenceTotal":7,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev 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