CVE-2026-54999
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk21th percentile - higher than 21% of all known CVEs
Summary
A race condition in Windows TCP/IP stack allows concurrent access to shared resources without proper synchronization. This enables an unauthorized attacker to execute code over an adjacent network.
Risk Assessment
An attacker on an adjacent network can remotely execute arbitrary code on the vulnerable Windows system, leading to full device compromise and potential lateral movement within the internal network.
Recommendation
Apply the security update released by Microsoft for Windows immediately. Restrict trust for traffic from adjacent networks and monitor for unusual network activity.
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Original NVD description (English source)
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over an adjacent network.