CVE-2024-12254: high-severity vulnerability in Python Software Foundation CPython
Unbounded memory buffering in SelectorSocketTransport.writelines()
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 1.9%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
Python Software Foundation · CPythonRelated CVEs — Python Software Foundation CPython
In the same product, most dangerous first.
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References
https://github.com/python/cpython/commit/71e8429ac8e2adc10084ab5ec29a62f4b6671a82https://github.com/python/cpython/commit/9aa0deb2eef2655a1029ba228527b152353135b5https://github.com/python/cpython/commit/e991ac8f2037d78140e417cc9a9486223eb3e786https://github.com/python/cpython/issues/127655https://github.com/python/cpython/pull/127656https://mail.python.org/archives/list/security-announce@python.org/thread/H4O3UBAOAQQXGT4RE3E4XQYR5XLROORB/https://security.netapp.com/advisory/ntap-20250404-0010/http://www.openwall.com/lists/oss-security/2024/12/06/1