CVE-2026-3298

EUVD-2026-24136
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
PSFCNA
8.8 HIGH
NETWORK
LOW
NONE
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
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
pythoncpython
3.11.0 ≤
𝑥
< 3.15.0
CNA
Common Weakness Enumeration
References
https://github.com/python/cpython/commit/1274766d3c29007ab77245a72abbf8dce2a9db4d
https://github.com/python/cpython/commit/27522b7d6e6588f03e61099dd858cd5a9314e2f2
https://github.com/python/cpython/commit/95633d2aad4721e25e4dfd9f43dfb6e1edcbd741
https://github.com/python/cpython/issues/148808
https://github.com/python/cpython/pull/148809
https://mail.python.org/archives/list/security-announce@python.org/thread/KWTPIQBOOOUNQP7UFSLBI437NJDFLA3F/