VulnerabilityAwaiting Analysis
CVE-2026-3298
The method "sock_recvfrom_into()" of "asyncio.ProacterEventLoop" (Windows only) was missing a boundary check for the data buffer when using nbytes parameter.
HIGH 8.8EPSS 0.39%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.8 HIGHCVSS: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/M
- EPSS
- 0.39% probability · 33th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Source
- cna@python.org
References
- https://github.com/python/cpython/commit/1274766d3c29007ab77245a72abbf8dce2a9db4d
- https://github.com/python/cpython/commit/27522b7d6e6588f03e61099dd858cd5a9314e2f2
- https://github.com/python/cpython/commit/6c8b85b3f1d83d5697ec19880960e1eacee56688
- https://github.com/python/cpython/commit/95633d2aad4721e25e4dfd9f43dfb6e1edcbd741
- https://github.com/python/cpython/commit/f5ca38739241fe7a40a4b116d5a8a1364dd6fea7
- 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/
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.