CVE-2026-3298

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.

EPSS — Exploit Prediction

0.0007

Probability of exploitation

0.20%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

References

Other 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/[email protected]/thread/KWTPIQBOOOUNQP7UFSLBI437NJDFLA3F/

Frequently Asked Questions

What is 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. This allowed for an out-of-bounds buffer write if data was larger than the buffer size. Non-Windows platforms are not affected.

How do I check if I'm vulnerable to CVE-2026-3298? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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