CVE-2021-33771
Actively exploited. CVE-2021-33771 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.
Microsoft Windows kernel contains an unspecified vulnerability that allows for privilege escalation.
CSIRTS triage
- What
- An unspecified vulnerability allows for privilege escalation.
- Who is affected
- Users of Microsoft Windows operating systems.
- Urgency
- Remediation is critical due to active exploitation and the severity of the vulnerability.
- Action
- Apply the latest security updates for Windows.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 93% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2021-33771: Microsoft Windows Kernel Privilege Escalation Vulnerabilitycisa-kev · 2021-11-03
External references
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