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Vulnerability details: VCID-8gac-u2vb-qkcq
Vulnerability ID VCID-8gac-u2vb-qkcq
Aliases CVE-2026-33230
GHSA-gfwx-w7gr-fvh7
Summary 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` 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. Commit 1c3f799607eeb088cab2491dcf806ae83c29ad8f fixes the issue.
Status Published
Exploitability 0.5
Weighted Severity 6.2
Risk 3.1
Affected and Fixed Packages Package 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 6.1 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33230.json
epss 0.00019 https://api.first.org/data/v1/epss?cve=CVE-2026-33230
epss 0.00019 https://api.first.org/data/v1/epss?cve=CVE-2026-33230
epss 0.00019 https://api.first.org/data/v1/epss?cve=CVE-2026-33230
cvssv3.1_qr MODERATE https://github.com/advisories/GHSA-gfwx-w7gr-fvh7
cvssv3.1 6.1 https://github.com/nltk/nltk
generic_textual MODERATE https://github.com/nltk/nltk
cvssv3.1 6.1 https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
generic_textual MODERATE https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
ssvc Track https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
cvssv3.1 6.1 https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
generic_textual MODERATE https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
ssvc Track https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
cvssv3.1 6.1 https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
cvssv3.1_qr MODERATE https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
generic_textual MODERATE https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
ssvc Track https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
cvssv3.1 6.1 https://nvd.nist.gov/vuln/detail/CVE-2026-33230
generic_textual MODERATE https://nvd.nist.gov/vuln/detail/CVE-2026-33230
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33230.json
https://api.first.org/data/v1/epss?cve=CVE-2026-33230
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-33230
https://github.com/nltk/nltk
https://nvd.nist.gov/vuln/detail/CVE-2026-33230
1131457 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1131457
1c3f799607eeb088cab2491dcf806ae83c29ad8f https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
2449825 https://bugzilla.redhat.com/show_bug.cgi?id=2449825
40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
GHSA-gfwx-w7gr-fvh7 https://github.com/advisories/GHSA-gfwx-w7gr-fvh7
GHSA-gfwx-w7gr-fvh7 https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
USN-8302-1 https://usn.ubuntu.com/8302-1/
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33230.json
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

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none

required

unchanged

changed

high

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none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/nltk/nltk
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

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none

required

unchanged

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high

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none

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low

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none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
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

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low

none

high

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none
Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-24T02:06:58Z/ Found at https://github.com/nltk/nltk/commit/1c3f799607eeb088cab2491dcf806ae83c29ad8f
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
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

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none
Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-24T02:06:58Z/ Found at https://github.com/nltk/nltk/commit/40d0bc1d484a3458d6a63ecb5ba4957ab16ba14e
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
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/ Found at https://github.com/nltk/nltk/security/advisories/GHSA-gfwx-w7gr-fvh7
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://nvd.nist.gov/vuln/detail/CVE-2026-33230
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
Exploit Prediction Scoring System (EPSS)
Percentile 0.0549
EPSS Score 0.00019
Published At June 11, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-06-11T16:49:46.473906+00:00 Vulnrichment Import https://github.com/cisagov/vulnrichment/blob/develop/2026/33xxx/CVE-2026-33230.json 38.6.0