CVE-2025-21334
Actively exploited. CVE-2025-21334 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-01-14) — 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 Hyper-V NT Kernel Integration VSP contains a use-after-free vulnerability that allows a local attacker to gain SYSTEM privileges.
CSIRTS triage
- What
- This component contains a use-after-free vulnerability that allows a local attacker to gain SYSTEM privileges.
- Who is affected
- Local users with access to the affected system are at risk.
- Urgency
- Remediation is critical due to active exploitation and high severity.
- Action
- Install the latest security updates from Microsoft.
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 72% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2025-21334: Microsoft Windows Hyper-V NT Kernel Integration VSP Use-After-Free Vulnerabilitycisa-kev · 2025-01-14
External references
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