Deserialization of Untrusted Data Affecting nltk package, versions <3.10.3-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.78% (54th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-NLTK-19233174
  • published23 Aug 2026
  • disclosed22 Aug 2026

Introduced: 22 Aug 2026

NewCVE-2026-71513  (opens in a new tab)
CWE-502  (opens in a new tab)

How to fix?

Upgrade Debian:unstable nltk to version 3.10.3-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nltk package and not the nltk package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1