CVE-2026-12199: CWE-306 Missing Authentication for Critical Function in nltk nltk/nltk
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.
AI Analysis
Technical Summary
CVE-2026-12199 is a high-severity vulnerability in nltk's WordNet Browser HTTP server component (nltk.app.wordnet_app) up to version 3.9.3. The server, when started in its default mode, listens on all network interfaces and accepts an unauthenticated GET request to the path '/SHUTDOWN%20THE%20SERVER'. Upon receiving this request, the server immediately terminates the process using os._exit(0), causing a denial of service. The root cause is the lack of authentication or protection mechanisms for this critical shutdown function, classified under CWE-306 (Missing Authentication for Critical Function).
Potential Impact
An unauthenticated remote attacker can cause a denial of service by shutting down the WordNet Browser HTTP server, impacting service availability. There is no confidentiality or integrity impact 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 a fix is available, avoid exposing the WordNet Browser HTTP server to untrusted networks or disable the server if not needed. Implement network-level access controls to restrict access to trusted users only.
CVE-2026-12199: CWE-306 Missing Authentication for Critical Function in nltk nltk/nltk
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.
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 nltk's WordNet Browser HTTP server component (nltk.app.wordnet_app) up to version 3.9.3. The server, when started in its default mode, listens on all network interfaces and accepts an unauthenticated GET request to the path '/SHUTDOWN%20THE%20SERVER'. Upon receiving this request, the server immediately terminates the process using os._exit(0), causing a denial of service. The root cause is the lack of authentication or protection mechanisms for this critical shutdown function, classified under CWE-306 (Missing Authentication for Critical Function).
Potential Impact
An unauthenticated remote attacker can cause a denial of service by shutting down the WordNet Browser HTTP server, impacting service availability. There is no confidentiality or integrity impact 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 a fix is available, avoid exposing the WordNet Browser HTTP server to untrusted networks or disable the server if not needed. Implement network-level access controls to restrict access to trusted users only.
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: 6/17/2026, 7:45:48 AM
Last enriched: 6/17/2026, 8:00:25 AM
Last updated: 6/17/2026, 5:24:55 PM
Views: 6
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