In CPython 3.13 and earlier, the tarfile module's data and tar extraction filters are vulnerable to crafted archives containing a hard link to a symbolic link. Such archives may cause extraction to modify the permissions or modification time of a file outside the destination directory, or expose the contents of that file within the extracted tree.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
Passive
Minimal interaction
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
python software foundation:cpython
References 7
https://github.com/python/cpython/commit/5a57248b22ad3b9aafcaaadae2c304a1923dae…
cna@python.org
https://github.com/python/cpython/issues/157190
cna@python.org
https://github.com/python/cpython/pull/157191
cna@python.org
https://mail.python.org/archives/list/security-announce@python.org/thread/EFJWG…
cna@python.org
http://www.openwall.com/lists/oss-security/2026/09/14/27
af854a3a-2127-422b-91ae-364da2661108
https://github.com/python/cpython/commit/b38be2e6cf9d989075ab73412c63e003ebad4f…
cna@python.org
https://github.com/python/cpython/commit/b8f23e307097552eaea2604383a12ab280520d…
cna@python.org