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.
Affected products
nltk: nltk
References9
- github.com/nltk/nltk/security/advisories/GHSA-jm6w-m3j8-898g ExploitVendor Advisory
- github.com/nltk/nltk/commit/bbaae83db86a0f49e00f5b0db44a7254c26… Patch
- access.redhat.com/errata/RHSA-2026:19712
- access.redhat.com/errata/RHSA-2026:24977
- access.redhat.com/errata/RHSA-2026:37275
- access.redhat.com/errata/RHSA-2026:65126
- access.redhat.com/security/cve/CVE-2026-33231
- bugzilla.redhat.com/show_bug.cgi?id=2449836
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33231…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 70 · as of 12 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
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