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


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
1.21% (67th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-NLTK-19257718
  • published26 Aug 2026
  • disclosed25 Aug 2026

Introduced: 25 Aug 2026

NewCVE-2026-79657  (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 versions before 3.10.3 contain a remote code execution vulnerability in allowlisted pickle loaders that trust entire module namespaces instead of specific safe callables. Attackers can craft malicious pickle payloads invoking dangerous in-namespace functions like ReppTokenizer._execute and numpy.f2py.crackfortran.myeval through pickle REDUCE to execute arbitrary commands during model or tokenizer artifact loading.

CVSS Base Scores

version 3.1