CVE-2026-71513 (GCVE-0-2026-71513)
Vulnerability from cvelistv5
Published
2026-08-22 13:34
Modified
2026-08-27 16:24
CWE
  • CWE-502 - Deserialization of Untrusted Data
Summary
NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. Attackers can craft untrusted transition-parser models that execute arbitrary commands when TransitionParser.parse loads the model through allowlisted_pickle_load.
Impacted products
Vendor Product Version
nltk nltk Version: 3.10.0   
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
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