Vulnerability in Python Software Foundation Cpython
CVE-2025-4435
When using a TarFile.errorlevel = 0 and extracting with a filter the documented behavior is that any filtered members would be skipped and not extracted. However the actual behavior of TarFile.errorlevel = 0 in affected versions is that the member would still be extracted and not skipped.
EPSS: 0.005 (39.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
Affected products
- Python Software Foundation Cpython — versions 3.10.0, 0, 3.14.0a1
Weakness classification (CWE)
Public proof-of-concept exploits
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 (patch)
- cna@python.org (patch)
- cna@python.org (patch)
- cna@python.org (patch)
- cna@python.org (patch)
Frequently asked questions
- What is CVE-2025-4435?
- CVE-2025-4435 is a high-severity vulnerability in Python Software Foundation Cpython, classified under Incorrect Calculation. CVSS score: 7.5/10. Published 2025-06-03.
- How severe is CVE-2025-4435?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-4435 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.