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 request (`/SHUTDOWN%20THE%20SERVER`) to terminate the process immediately via `os._exit(0)`. This results in a denial of service, impacting service availability. The issue arises due to insufficient authentication and protection mechanisms for critical server functions.
History

Thu, 18 Jun 2026 16:45:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Thu, 18 Jun 2026 04:45:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 17 Jun 2026 09:15:00 +0000

Type Values Removed Values Added
First Time appeared Nltk
Nltk nltk/nltk
Vendors & Products Nltk
Nltk nltk/nltk

Wed, 17 Jun 2026 07:45:00 +0000

Type Values Removed Values Added
Description 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 request (`/SHUTDOWN%20THE%20SERVER`) to terminate the process immediately via `os._exit(0)`. This results in a denial of service, impacting service availability. The issue arises due to insufficient authentication and protection mechanisms for critical server functions.
Title Unauthenticated Denial of Service in nltk.app.wordnet_app
Weaknesses CWE-306
References
Metrics cvssV3_0

{'score': 7.5, 'vector': 'CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: @huntr_ai

Published:

Updated: 2026-06-17T14:21:08.627Z

Reserved: 2026-06-14T09:15:42.775Z

Link: CVE-2026-12199

cve-icon Vulnrichment

Updated: 2026-06-17T14:21:04.329Z

cve-icon NVD

No data.

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-06-17T07:13:14Z

Links: CVE-2026-12199 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-06-18T18:15:02Z