Vigie VulnDBEuropean-hosted Vulnerability DB

CVE-2025-4138

Bypassing extraction filter to create symlinks to arbitrary targets outside extraction directory

At a glance

Severity
HIGH 7.5
EPSS
EPSS 1.39 % · percentile 72 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
PSF
NVD status
Deferred

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.

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NPSF
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NNVD · cna@python.org (Secondary)

Weaknesses (CWE)

European references

CERT-FR advisories

Affected products

ProductVersions
Python Software Foundation · CPythonaffected 0 < 3.9.23 ; affected 3.10.0 < 3.10.18 ; affected 3.11.0 < 3.11.13 ; affected 3.12.0 < 3.12.11 ; affected 3.13.0 < 3.13.4 ; affected 3.14.0a1 < 3.14.0b3

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD