CVE-2024-12254 Information

Description

Starting in Python 3.12.0 the asyncio._SelectorSocketTransport.writelines() method would not \pause\ writing and signal to the Protocol to drain the buffer to the wire once the write buffer reached the \high-water mark. Because of this Protocols would not periodically drain the write buffer potentially leading to memory exhaustion.

This vulnerability likely impacts a small number of users you must be using Python 3.12.0 or later on macOS or Linux using the asyncio module with protocols and using .writelines() method which had new zero-copy-on-write behavior in Python 3.12.0 and later. If not all of these factors are true then your usage of Python is unaffected.

Reference

http://www.openwall.com/lists/oss-security/2024/12/06/1 https://github.com/python/cpython/commit/71e8429ac8e2adc10084ab5ec29a62f4b6671a82 https://github.com/python/cpython/commit/9aa0deb2eef2655a1029ba228527b152353135b5 https://github.com/python/cpython/issues/127655 https://github.com/python/cpython/pull/127656 https://mail.python.org/archives/list/security-announce@python.org/thread/H4O3UBAOAQQXGT4RE3E4XQYR5XLROORB/