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Product · nltk

nltk/nltk

11 known vulnerabilities.

nltk/nltk at a glance

Last 12 months
9
Critical · all time
2
Exploited · all time
0
Public exploit · all time
2
New vulnerabilities per month · last 12 months
0 3 5 December 2025: 0 vulnerabilities Dec 2025 January 2026: 0 vulnerabilities February 2026: 1 vulnerability, 1 critical March 2026: 3 vulnerabilities, 1 critical Mar April 2026: 0 vulnerabilities May 2026: 0 vulnerabilities June 2026: 1 vulnerability Jun July 2026: 1 vulnerability August 2026: 3 vulnerabilities September 2026: 0 vulnerabilities Sep October 2026: 0 vulnerabilities November 2026: 0 vulnerabilities
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11 results · Feed

  • Low 3.7

    Server-Side Request Forgery (SSRF) in nltk/nltk

    A Server-Side Request Forgery (SSRF) vulnerability exists in nltk/nltk versions 3.9.4 and the current develop branch. The `nltk.pathsec.validate_network_url()` function, intended to prevent SSRF by rejecting internal network addresses, fails to reject IPs in …

  • Medium 5.3

    Improper Access Control in nltk/nltk

    A vulnerability in `nltk.downloader` in nltk/nltk versions <= 3.9.4 allows for cross-package resource and model poisoning. The downloader extracts package archives into shared namespaces such as `corpora/` and `taggers/` instead of package-isolated roots, and…

  • Medium 5.3

    Improper Input Validation in nltk/nltk

    In nltk version 3.9.4, the `nltk.downloader.Downloader._download_package()` function writes downloaded package bytes to disk and may extract them before enforcing SHA-256 or MD5 checksum validation. This allows an attacker to tamper with the package response …

  • High 7.8

    Untrusted JAR Code Execution in Multiple Stanford Interface Classes in nltk/nltk

    In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept …

  • High 7.5

    Unauthenticated Denial of Service in nltk.app.wordnet_app

    A vulnerability in `nltk.app.wordnet_app` up to version 3.9.3 allows unauthenticated remote shutdown of the local WordNet Browser HTTP server when started in its default mode. The server listens on all interfaces and processes a specific unauthenticated GET r…

  • High 8.6

    Arbitrary File Read via Absolute Path Input in nltk.util.filestring()

    A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attac…

  • Critical 10.0
    CVE-2026-0848 Public exploit

    Arbitrary Code Execution in NLTK StanfordSegmenter via Untrusted JAR Loading

    NLTK versions <=3.9.2 are vulnerable to arbitrary code execution due to improper input validation in the StanfordSegmenter module. The module dynamically loads external Java .jar files without verification or sandboxing. An attacker can supply or replace the …

  • High 8.6
    CVE-2026-0847 Public exploit

    Path Traversal in nltk/nltk

    A vulnerability in NLTK versions up to and including 3.9.2 allows arbitrary file read via path traversal in multiple CorpusReader classes, including WordListCorpusReader, TaggedCorpusReader, and BracketParseCorpusReader. These classes fail to properly sanitiz…

  • Critical 10.0

    Zip Slip Vulnerability in nltk/nltk Leading to Remote Code Execution

    A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to cra…

  • High 7.5

    Inefficient Regular Expression Complexity in nltk/nltk

    nltk is vulnerable to Inefficient Regular Expression Complexity

  • High 7.5

    Inefficient Regular Expression Complexity in nltk/nltk

    nltk is vulnerable to Inefficient Regular Expression Complexity