{"id":"PYSEC-2026-2236","details":"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.","aliases":["CVE-2026-33231","GHSA-jm6w-m3j8-898g"],"modified":"2026-07-13T07:15:50.554652709Z","published":"2026-03-20T23:16:46.850Z","references":[{"type":"WEB","url":"https://access.redhat.com/security/cve/CVE-2026-33231"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33231.json"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19712"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24977"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:37275"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2449836"},{"type":"FIX","url":"https://github.com/nltk/nltk/commit/bbaae83db86a0f49e00f5b0db44a7254c268de9b"},{"type":"EVIDENCE","url":"https://github.com/nltk/nltk/security/advisories/GHSA-jm6w-m3j8-898g"}],"affected":[{"package":{"name":"nltk","ecosystem":"PyPI","purl":"pkg:pypi/nltk"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.4"}]}],"versions":["0.8","0.9","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","2.0.1","2.0.1rc1","2.0.1rc2-git","2.0.1rc3","2.0.1rc4","2.0.2","2.0.3","2.0.4","2.0.5","2.0b4","2.0b5","2.0b6","2.0b7","2.0b8","2.0b9","3.0.0","3.0.0b1","3.0.0b2","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.9","3.9.1","3.9.2","3.9.3","3.9b1"],"ecosystem_specific":{},"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/nltk/PYSEC-2026-2236.yaml"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}