CVE-2026-4360

In the Tarfile.extract() function, the filter parameter is not passed properly when extracting hardlinks. An affected system that extracts content from untrusted tar files could end up writing files with an unexpected uid/gid despite the user passing filter='data' to the extract() function.

Score

CVSS 3.1 5.3 Medium

Status

Modified - cna@python.org

Published

2026-06-30

Last modified

2026-10-25

Weaknesses

CWE-281

Affected products

• Python (Python)
• Cpython (Python Software Foundation)

References

• https://mail.python.org/archives/list/security-announce@python.org/thread/TWZW2PC2AZOV6FENIHFSRC63OM7MBGSB/
• https://github.com/python/cpython/pull/151988
• https://github.com/python/cpython/issues/151987
• https://github.com/python/cpython/commit/5e0ef3f1afe892e4f64eb83368db57ac4c40cba0
• https://github.com/python/cpython/commit/7b57e8d51446297b8c7c482d224bc5f1938e4301
• https://github.com/python/cpython/commit/7ccdbaba2c54250a70d7f25632152df7655a5e0a
• https://github.com/python/cpython/commit/eee3ddf0ca10283cc7fea724aae9cd8665f8d15e
• https://github.com/python/cpython/commit/d2b2f5eacab4dd48446b63340613b05dcbbf0b44
• https://github.com/python/cpython/commit/cf23b9153181062150d061468b6d24af33fe214f
• https://github.com/python/cpython/commit/0367912be336348b30572f8029cec4a282782d92