CVE-2026-3298

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Source
https://cve.org/CVERecord?id=CVE-2026-3298
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-3298.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-3298
Aliases
Downstream
Related
Published
2026-04-21T14:45:01.919Z
Modified
2026-07-08T05:03:09.180952708Z
Severity
  • 8.8 (High) CVSS_V4 - 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 CVSS Calculator
Summary
Out-of-bounds write in Windows asyncio.ProacterEventLoop.sock_recvfrom_into() when using nbytes
Details

The method "sockrecvfrominto()" 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.

Database specific 
{
    "cna_assigner": "PSF",
    "cwe_ids": [
        "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/3xxx/CVE-2026-3298.json"
}
References

Affected packages

Git / github.com/python/cpython

Affected ranges

Type
GIT
Repo
https://github.com/python/cpython
Events
Introduced
deaf509e8fc6e0363bd6f26d52ad42f976ec42f2
Fixed
fd17997c3866d61e0e7bd8201b1d8f35b40a40bd
Introduced
b092705907c758d4f9742028652c9802f9f03dd3
Fixed
a68a9190498a16ab1a5c9012ef5a70df81a5b328
Introduced
f31a89bb901067dd105b00cfa90523cf7ffdbbdd
Fixed
f31a89bb901067dd105b00cfa90523cf7ffdbbdd
Database specific 
{
    "source": "AFFECTED_FIELD",
    "extracted_events": [
        {
            "introduced": "3.11.0"
        },
        {
            "fixed": "3.13.14"
        },
        {
            "introduced": "3.14.0a1"
        },
        {
            "fixed": "3.14.5rc1"
        },
        {
            "introduced": "3.15.0a1"
        },
        {
            "fixed": "3.15.0b1"
        }
    ]
}

Affected versions

v3.*
v3.14.0
v3.14.0b1
v3.14.0b2
v3.14.0b3
v3.14.0b4
v3.14.0rc1
v3.14.0rc2
v3.14.0rc3
v3.14.1
v3.14.2
v3.14.3
v3.14.4
v3.15.0a1
v3.15.0a2
v3.15.0a3
v3.15.0a4
v3.15.0a5
v3.15.0a6
v3.15.0a7
v3.15.0a8

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-3298.json"