Not scored yet
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.
What this means for your business
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 35% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 5.7
- Weakness
- CWE-22
- Assigned by
- cna@python.org
Dates
- Published
- 2026-09-11
- Last modified
- 2026-09-16
- Sources
- NVD
References
- 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