CVE-2026-3298highCWE-787

CVE-2026-3298: high-severity vulnerability in Python Software Foundation CPython

Out-of-bounds write in Windows asyncio.ProacterEventLoop.sock_recvfrom_into() when using nbytes

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.8epss 0.4%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
Affected products
Python Software Foundation · CPython
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