Missing Authentication for Critical Function Affecting nltk package, versions [,3.9.4)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-PYTHON-NLTK-17391908
- published21 Jun 2026
- disclosed17 Jun 2026
- creditleduckhuong
Introduced: 17 Jun 2026
NewCVE-2026-12199 (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 via the nltk.app.wordnet_app module. An attacker can cause the server to shut down and disrupt service availability by sending a specially crafted GET request to the WordNet Browser HTTP server when it is running in its default mode.