Missing Authentication for Critical Function Affecting nltk package, versions [0,3.9.4)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
0.88% (55th percentile)

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  • Snyk IDSNYK-PYTHON-NLTK-15692504
  • published19 Mar 2026
  • disclosed19 Mar 2026
  • creditleduckhuong

Introduced: 19 Mar 2026

CVE-2026-33231  (opens in a new tab)
CWE-306  (opens in a new tab)

How to fix?

Upgrade nltk to version 3.9.4 or higher.

Overview

nltk is a Natural Language Toolkit (NLTK) is a Python package for natural language processing.

Affected versions of this package are vulnerable to Missing Authentication for Critical Function in WordNet Browser HTTP server in default configuration. An attacker can cause the service to terminate immediately by sending a specially crafted unauthenticated HTTP GET request (e.g. http://127.0.0.1:8004/SHUTDOWN%20THE%20SERVER) to the listening port.

References

CVSS Base Scores

version 4.0
version 3.1