CVE-2026-33231CWE-306

CVE-2026-33231

High · published March 21, 2026

CVSS v3.1
7.5
EPSS
2%
Percentile
74.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.01515 · 74.3th percentile
Weakness
CWE-306 · Missing Authentication for Critical Function
Published
2026-03-21T03:16Z
Affected products (1)
ProductVersionsFixed in
nltk/nltk≤ 3.9.3—
References (9)
https://github.com/nltk/nltk/commit/bbaae83db86a0f49e00f5b0db44a7254c268de9b · [email protected]https://github.com/nltk/nltk/security/advisories/GHSA-jm6w-m3j8-898g · [email protected]https://access.redhat.com/errata/RHSA-2026:19712 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:24977 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:37275 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:65126 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/security/cve/CVE-2026-33231 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://bugzilla.redhat.com/show_bug.cgi?id=2449836 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33231.json · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
EPSS history
Timeline
  • 20 MAR 22:45Z
    NLTK has unauthenticated remote shutdown in nltk.app.wordnet_app
    cvelistv5