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4 vulnerabilities found for nltk by nltk
CVE-2026-33236 (GCVE-0-2026-33236)
Vulnerability from cvelistv5
Published
2026-03-20 22:47
Modified
2026-03-23 16:46
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Summary
NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. In versions 3.9.3 and prior, the NLTK downloader does not validate the `subdir` and `id` attributes when processing remote XML index files. Attackers can control a remote XML index server to provide malicious values containing path traversal sequences (such as `../`), which can lead to arbitrary directory creation, arbitrary file creation, and arbitrary file overwrite. Commit 89fe2ec2c6bae6e2e7a46dad65cc34231976ed8a patches the issue.
References
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CVE-2026-33231 (GCVE-0-2026-33231)
Vulnerability from cvelistv5
Published
2026-03-20 22:45
Modified
2026-03-25 13:43
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-306 - Missing Authentication for Critical Function
Summary
NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. In versions 3.9.3 and prior, `nltk.app.wordnet_app` allows unauthenticated remote shutdown of the local WordNet Browser HTTP server when it is started in its default mode. A simple `GET /SHUTDOWN%20THE%20SERVER` request causes the process to terminate immediately via `os._exit(0)`, resulting in a denial of service. Commit bbaae83db86a0f49e00f5b0db44a7254c268de9b patches the issue.
References
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CVE-2026-33230 (GCVE-0-2026-33230)
Vulnerability from cvelistv5
Published
2026-03-20 22:43
Modified
2026-03-24 02:07
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Summary
NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. In versions 3.9.3 and prior, `nltk.app.wordnet_app` contains a reflected cross-site scripting issue in the `lookup_...` route. A crafted `lookup_<payload>` URL can inject arbitrary HTML/JavaScript into the response page because attacker-controlled `word` data is reflected into HTML without escaping. This impacts users running the local WordNet Browser server and can lead to script execution in the browser origin of that application. Commit 1c3f799607eeb088cab2491dcf806ae83c29ad8f fixes the issue.
References
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CVE-2021-43854 (GCVE-0-2021-43854)
Vulnerability from cvelistv5
Published
2021-12-23 17:55
Modified
2024-08-04 04:10
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-400 - Uncontrolled Resource Consumption
Summary
NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. Versions prior to 3.6.5 are vulnerable to regular expression denial of service (ReDoS) attacks. The vulnerability is present in PunktSentenceTokenizer, sent_tokenize and word_tokenize. Any users of this class, or these two functions, are vulnerable to the ReDoS attack. In short, a specifically crafted long input to any of these vulnerable functions will cause them to take a significant amount of execution time. If your program relies on any of the vulnerable functions for tokenizing unpredictable user input, then we would strongly recommend upgrading to a version of NLTK without the vulnerability. For users unable to upgrade the execution time can be bounded by limiting the maximum length of an input to any of the vulnerable functions. Our recommendation is to implement such a limit.
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"datePublished": "2021-12-23T17:55:11.000Z",
"dateReserved": "2021-11-16T00:00:00.000Z",
"dateUpdated": "2024-08-04T04:10:16.281Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}