CVE-2026-3298
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk33th percentile - higher than 33% of all known CVEs
Summary
The sock_recvfrom_into() method in asyncio.ProactorEventLoop (Windows only) lacked a boundary check for the data buffer when using the nbytes parameter, allowing an out-of-bounds buffer write if data was larger than the buffer size.
Risk Assessment
An attacker may cause application crashes or potentially execute arbitrary code in the process context.
Recommendation
Update Python to a version that includes a fix for this vulnerability (if applicable).
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Original NVD description (English source)
The method "sock_recvfrom_into()" of "asyncio.ProacterEventLoop" (Windows only) was missing a boundary check for the data buffer when using nbytes parameter. This allowed for an out-of-bounds buffer write if data was larger than the buffer size. Non-Windows platforms are not affected.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

