CVE-2025-4138
Allows the extraction filter to be ignored, allowing symlink targets to point outside the destination directory, and the modification of some file metadata.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 1.39% probability · 72th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- cna@python.org
EPSS 1.4% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://gist.github.com/sethmlarson/52398e33eff261329a0180ac1d54f42f
- https://github.com/python/cpython/commit/19de092debb3d7e832e5672cc2f7b788d35951da
- https://github.com/python/cpython/commit/28463dba112af719df1e8b0391c46787ad756dd9
- https://github.com/python/cpython/commit/3612d8f51741b11f36f8fb0494d79086bac9390a
- https://github.com/python/cpython/commit/4633f3f497b1ff70e4a35b6fe2c907cbe2d4cb2e
- https://github.com/python/cpython/commit/9c1110ef6652687d7c55f590f909720eddde965a
- https://github.com/python/cpython/commit/9e0ac76d96cf80b49055f6d6b9a6763fb9215c2a
- https://github.com/python/cpython/commit/aa9eb5f757ceff461e6e996f12c89e5d9b583b01
- https://github.com/python/cpython/commit/dd8f187d0746da151e0025c51680979ac5b4cfb1
- https://github.com/python/cpython/issues/135034
- https://github.com/python/cpython/pull/135037
- https://mail.python.org/archives/list/security-announce@python.org/thread/MAXIJJCUUMCL7ATZNDVEGGHUMQMUUKLG/
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.