Path Traversal in Python Software Foundation Cpython
CVE-2025-4517
Allows arbitrary filesystem writes outside the extraction directory during extraction with filter="data". 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.
Vulnerability class: Path Traversal (Directory Traversal)
EPSS: 0.012 (65.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.4 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L.
Affected products
- Python Software Foundation Cpython — versions 3.10.0, 0, 3.14.0a1
Weakness classification (CWE)
Public proof-of-concept exploits
- AzureADTrent/CVE-2025-4517-POC
- 0xDTC/CVE-2025-4517-tarfile-PATH_MAX-bypass
- StealthByte0/CVE-2025-4517-poc
- AnimePrincess420/CVE-2025-4517-PoC
- estebanzarate/CVE-2025-4517-Python-tarfile-filter-data-Bypass-PoC
- Rohitberiwala/PyPath-Escape-CVE-2025-4517-Exploit-Research
- bgutowski/CVE-2025-4517-POC-Sudoers
- kerburenthusiasm/CVE-2025-4517-PoC
- fkie-cad/nvd-json-data-feeds
- 11notes/docker-paperless-ngx
References
- cna@python.org (issue-tracking)
- cna@python.org (patch)
- cna@python.org (vendor-advisory)
- cna@python.org (patch)
- cna@python.org (patch)
- cna@python.org (mitigation)
- cna@python.org (patch)
- cna@python.org (patch)
- cna@python.org (patch)
- cna@python.org (patch)
Frequently asked questions
- What is CVE-2025-4517?
- CVE-2025-4517 is a critical-severity vulnerability in Python Software Foundation Cpython, classified under Path Traversal. CVSS score: 9.4/10. Published 2025-06-03.
- How severe is CVE-2025-4517?
- Critical severity. CVSS v3 base score is 9.4 out of 10.
- Is CVE-2025-4517 known to be exploited?
- 12 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.