CVE-2026-87910

When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.

CVSS

No CVSS.

References

Link	Resource
https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b
https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2
https://github.com/python/cpython/issues/157265
https://github.com/python/cpython/pull/157266
https://mail.python.org/archives/list/security-announce@python.org/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ/
http://www.openwall.com/lists/oss-security/2026/09/11/8

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 18:16

Updated : 2026-09-12 01:16

NVD link : CVE-2026-87910

Mitre link : CVE-2026-87910

CVE.ORG link : CVE-2026-87910

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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