{"schemaVersion":3,"id":"CVE-2026-12199","aliases":["UBUNTU-CVE-2026-12199","DEBIAN-CVE-2026-12199"],"status":"published","duplicateOf":null,"title":null,"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. 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