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CVE-2026-87910 (GCVE-0-2026-87910)

Vulnerability from cvelistv5 – Published: 2026-09-11 17:27 – Updated: 2026-09-12 00:31
VLAI
Title
tarfile hardlink fallback ignores custom extraction filter rejection via None
Summary
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.
Severity
5.7 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-11 19:23 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Python Software Foundation CPython Affected: 0 , < 3.15.0 (python)
guessed Create a notification for this product.
Credits
William Woodruff (https://github.com/woodruffw) Zanie Blue (https://github.com/zanieb) Petr Viktorin (https://github.com/encukou) Stan Ulbrych (https://github.com/StanFromIreland)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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