CVE-2026-33231

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/commit/bbaae83db86a0f49e00f5b0db44a7254c268de9b	Patch
https://github.com/nltk/nltk/security/advisories/GHSA-jm6w-m3j8-898g	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-20 23:16

Updated : 2026-03-23 19:15

NVD link : CVE-2026-33231

Mitre link : CVE-2026-33231

CVE.ORG link : CVE-2026-33231

JSON object : View

Products Affected

nltk

nltk

CWE

CWE-306

Missing Authentication for Critical Function

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