CVE-2025-4138

Description

Allows the extraction filter to be ignored, allowing symlink targets to point outside the destination directory, and the modification of some file metadata. You are affected by this vulnerability if using the tarfile module to extract untrusted tar archives using TarFile.extractall() or TarFile.extract() using the filter= parameter with a value of "data" or "tar". See the tarfile extraction filters documentation https://docs.python.org/3/library/tarfile.html#tarfile-extraction-filter for more information. Note that for Python 3.14 or later the default value of filter= changed from "no filtering" to `"data", so if you are relying on this new default behavior then your usage is also affected. Note that none of these vulnerabilities significantly affect the installation of source distributions which are tar archives as source distributions already allow arbitrary code execution during the build process. However when evaluating source distributions it's important to avoid installing source distributions with suspicious links.

How to fix CVE-2025-4138

To remediate CVE-2025-4138, upgrade the affected package to a fixed version below.

—upgrade to 3.11.13-r0 or later
—upgrade to 3.12.11-r0 or later
—upgrade to 3.9.23 or later
—upgrade to 3.9.23 or later
—upgrade to 3.9.23 or later
—no fix listed
—upgrade to 3.13.4-1 or later

Is CVE-2025-4138 being exploited?

Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.

Affected packages (7)

from 0, < 3.11.13-r0
from 0, < 3.12.11-r0
from 0, < 3.9.23, >= 3.10.0, < 3.10.18, >= 3.11.0, < 3.11.13, >= 3.12.0, < 3.12.11, >= 3.13.0, < 3.13.4
from 0, < 3.9.23, >= 3.10.0, < 3.10.18, >= 3.11.0, < 3.11.13, >= 3.12.0, < 3.12.11, >= 3.13.0, < 3.13.4
from 0, < 3.9.23, >= 3.10.0, < 3.10.18, >= 3.11.0, < 3.11.13, >= 3.12.0, < 3.12.11, >= 3.13.0, < 3.13.4
from 0
from 0, < 3.13.4-1

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 3.1	HIGH7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N