| Name | CVE-2024-12254 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 1089235, 1089236 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u5 | fixed |
| bookworm (security) | 3.11.2-6+deb12u3 | fixed | |
| python3.12 (PTS) | sid, trixie | 3.12.8-5 | fixed |
| python3.13 (PTS) | sid, trixie | 3.13.1-3 | fixed |
| python3.9 (PTS) | bullseye | 3.9.2-1 | fixed |
| bullseye (security) | 3.9.2-1+deb11u2 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| python3.11 | source | (unstable) | (not affected) | |||
| python3.12 | source | (unstable) | 3.12.8-2 | 1089236 | ||
| python3.13 | source | (unstable) | 3.13.1-2 | 1089235 | ||
| python3.9 | source | (unstable) | (not affected) |
- python3.11 <not-affected> (Vulnerable code introduced in 3.12)
- python3.9 <not-affected> (Vulnerable code introduced in 3.12)
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/
https://github.com/python/cpython/commit/71e8429ac8e2adc10084ab5ec29a62f4b6671a82 (3.13-branch)
https://github.com/python/cpython/commit/9aa0deb2eef2655a1029ba228527b152353135b5 (3.12-branch)