Improper Extraction Behavior in Python TarFile Module
CVE-2025-4435

7.5HIGH

Key Information:

Vendor

Python Software Foundation

Status
Cpython
Vendor
CVE Published:
3 June 2025

What is CVE-2025-4435?

In the TarFile module of Python, a flaw exists when TarFile.errorlevel is set to 0 while extracting files with a filter. Expected behavior dictates that filtered members should be omitted from extraction. However, a flaw in the processing logic leads to these members being extracted nonetheless, causing unintended data exposure. This can potentially lead to security concerns if sensitive information is inadvertently extracted.

Affected Version(s)

CPython 0 < 3.9.23

CPython 3.10.0 < 3.10.18

CPython 3.11.0 < 3.11.13

References

https://github.com/python/cpython/issues/135034
issue-tracking
https://github.com/python/cpython/pull/135037
patch
https://mail.python.org/archives/list/security-announce@p...
vendor-advisory

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Chuck Woodraska
Petr Viktorin
Serhiy Storchaka
Hugo van Kemenade
Ɓukasz Langa
Thomas Wouters
Seth Larson
.
CVE-2025-4435 : Improper Extraction Behavior in Python TarFile Module