Description
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.
References8
- github.com/python/cpython/commit/1274766d3c29007ab77245a72abbf8…
- github.com/python/cpython/commit/27522b7d6e6588f03e61099dd858cd…
- github.com/python/cpython/commit/6c8b85b3f1d83d5697ec19880960e1…
- github.com/python/cpython/commit/95633d2aad4721e25e4dfd9f43dfb6…
- github.com/python/cpython/commit/f5ca38739241fe7a40a4b116d5a8a1…
- github.com/python/cpython/issues/148808
- github.com/python/cpython/pull/148809
- mail.python.org/archives/list/[email protected]/thre…
Metrics
- CVSS 4.0
-
8.8
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 34 · as of 13 November 2026
- CWE
- CWE-787
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