CVE-2026-3298
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% 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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The incremental HTML parser (html.parser.HTMLParser) allows CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
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.