Staging Environment: Content and features may be unstable or change without notice.
Advisory details: gitlab / pypi/nltk/CVE-2026-33230
Advisory ID gitlab/pypi/nltk/CVE-2026-33230
Aliases CVE-2026-33230
GHSA-gfwx-w7gr-fvh7
Summary Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in nltk `nltk.app.wordnet_app` contains a reflected cross-site scripting issue in the `lookup_...` route. A crafted `lookup_<payload>` URL can inject arbitrary HTML/JavaScript into the response page because attacker-controlled `word` data is reflected into HTML without escaping. This impacts users running the local WordNet Browser server and can lead to script execution in the browser origin of that application.
Status Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (3)
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3.1 https://gitlab.com/gitlab-org/advisories-community/-/blob/main/pypi/nltk/CVE-2026-33230.yml
Reference id Reference type URL
https://github.com/nltk/nltk
1c3f799607eeb088cab2491dcf806ae83c29ad8f Other https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e Other https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
CVE-2026-33230 https://nvd.nist.gov/vuln/detail/CVE-2026-33230
GHSA-gfwx-w7gr-fvh7 https://github.com/advisories/GHSA-gfwx-w7gr-fvh7
GHSA-gfwx-w7gr-fvh7 Other https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://gitlab.com/gitlab-org/advisories-community/-/blob/main/pypi/nltk/CVE-2026-33230.yml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-24T02:06:58Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/33xxx/CVE-2026-33230.json

Source Advisory: vulnrichment/CVE-2026-33230

View SSVC decision tree 
[{'Exploitation': 'poc'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]