{"cve":"CVE-2026-33231","nvd":{"published":"2026-03-20T23:16:46.850","modified":"2026-09-09T13:19:24.380","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-306"],"references":["https://github.com/nltk/nltk/commit/bbaae83db86a0f49e00f5b0db44a7254c268de9b","https://github.com/nltk/nltk/security/advisories/GHSA-jm6w-m3j8-898g","https://access.redhat.com/errata/RHSA-2026:19712","https://access.redhat.com/errata/RHSA-2026:24977","https://access.redhat.com/errata/RHSA-2026:37275"],"products":["nltk:nltk"],"source":"nvd","synced_at":"2026-10-19T22:26:19.218427112+00:00"},"epss":{"cve":"CVE-2026-33231","score":0.01236,"percentile":0.69092,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-jm6w-m3j8-898g","url":"https://osv.dev/vulnerability/GHSA-jm6w-m3j8-898g","summary":"Unauthenticated remote shutdown in nltk.app.wordnet_app","modified":"2026-09-10T03:50:39.952342228Z","packages":[{"ecosystem":"PyPI","name":"nltk","purl":"pkg:pypi/nltk","ranges":["<3.9.4"],"fixed":["3.9.4"]}]},{"id":"PYSEC-2026-2236","url":"https://osv.dev/vulnerability/PYSEC-2026-2236","summary":"","modified":"2026-07-13T07:15:50.554652709Z","packages":[{"ecosystem":"PyPI","name":"nltk","purl":"pkg:pypi/nltk","ranges":["<3.9.4"],"fixed":["3.9.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}