Time-of-check Time-of-use (TOCTOU) Race Condition Affecting nltk package, versions [0,]
Threat Intelligence
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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- published8 Aug 2026
- disclosed7 Aug 2026
- creditUnknown
Introduced: 7 Aug 2026
NewCVE-2026-12261 (opens in a new tab)How to fix?
There is no fixed version for nltk.
Overview
nltk is a Natural Language Toolkit (NLTK) is a Python package for natural language processing.
Affected versions of this package are vulnerable to Time-of-check Time-of-use (TOCTOU) Race Condition via the downloader process. An attacker can compromise data integrity by causing package archives to be extracted into shared namespaces before integrity validation, which may overwrite trusted resources in machine learning pipelines and environments sensitive to reproducibility. This is only exploitable if a user interacts with the downloader and downloads a malicious package.