CVE-2026-12199: CWE-306 Missing Authentication for Critical Function in nltk nltk/nltk
A vulnerability in nltk's WordNet Browser HTTP server (up to version 3.9.3) allows unauthenticated remote shutdown via a specific GET request, causing denial of service. The server listens on all interfaces and lacks authentication for this critical function. This issue impacts service availability by terminating the server process immediately.
AI Analysis
Technical Summary
CVE-2026-12199 is a high-severity vulnerability in the nltk package, specifically in the nltk.app.wordnet_app component up to version 3.9.3. The local WordNet Browser HTTP server, when started in default mode, listens on all network interfaces and processes an unauthenticated GET request to the path '/SHUTDOWN%20THE%20SERVER'. This request triggers an immediate process termination using os._exit(0), resulting in a denial of service. The root cause is missing authentication for this critical function, classified under CWE-306 (Missing Authentication for Critical Function). No official patch or remediation level has been provided as of the published date.
Potential Impact
The vulnerability allows any unauthenticated remote attacker to shut down the WordNet Browser HTTP server, causing denial of service and loss of availability for users relying on this service. There is no impact on confidentiality or integrity reported. The server process terminates immediately upon receiving the crafted request.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should avoid exposing the WordNet Browser HTTP server to untrusted networks or restrict access to trusted hosts only. Consider disabling or not using the server in default mode if remote access is not required.
CVE-2026-12199: CWE-306 Missing Authentication for Critical Function in nltk nltk/nltk
Description
A vulnerability in nltk's WordNet Browser HTTP server (up to version 3.9.3) allows unauthenticated remote shutdown via a specific GET request, causing denial of service. The server listens on all interfaces and lacks authentication for this critical function. This issue impacts service availability by terminating the server process immediately.
CVSS v3.0
Score 7.5high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12199 is a high-severity vulnerability in the nltk package, specifically in the nltk.app.wordnet_app component up to version 3.9.3. The local WordNet Browser HTTP server, when started in default mode, listens on all network interfaces and processes an unauthenticated GET request to the path '/SHUTDOWN%20THE%20SERVER'. This request triggers an immediate process termination using os._exit(0), resulting in a denial of service. The root cause is missing authentication for this critical function, classified under CWE-306 (Missing Authentication for Critical Function). No official patch or remediation level has been provided as of the published date.
Potential Impact
The vulnerability allows any unauthenticated remote attacker to shut down the WordNet Browser HTTP server, causing denial of service and loss of availability for users relying on this service. There is no impact on confidentiality or integrity reported. The server process terminates immediately upon receiving the crafted request.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should avoid exposing the WordNet Browser HTTP server to untrusted networks or restrict access to trusted hosts only. Consider disabling or not using the server in default mode if remote access is not required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- @huntr_ai
- Date Reserved
- 2026-06-14T09:15:42.775Z
- Cvss Version
- 3.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3250ac0b89be6888f7d50d
Added to database: 06/17/2026, 07:45:48 UTC
Last enriched: 06/24/2026, 16:36:52 UTC
Last updated: 08/01/2026, 03:13:38 UTC
Views: 73
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