VDB-352233 · CVE-2026-33231 · GHSA-jm6w-m3j8-898g

NLTK up to 3.9.3 nltk.app.wordnet_app missing authentication

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3	$0-$5k	0.00

Summaryinfo

A vulnerability was found in NLTK up to 3.9.3. It has been rated as critical. This affects the function nltk.app.wordnet_app. Performing a manipulation results in missing authentication. This vulnerability was named CVE-2026-33231. The attack may be initiated remotely. There is no available exploit. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability classified as critical has been found in NLTK up to 3.9.3. This affects the function nltk.app.wordnet_app. The manipulation with an unknown input leads to a missing authentication vulnerability. CWE is classifying the issue as CWE-306. The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. This is going to have an impact on availability. The summary by CVE 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 advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-33231 since 03/18/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 303260 (Linux Distros Unpatched Vulnerability : CVE-2026-33231), which helps to determine the existence of the flaw in a target environment.

Applying the patch bbaae83db86a0f49e00f5b0db44a7254c268de9b is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the databases at Tenable (303260) and CERT Bund (WID-SEC-2026-0895). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

IBM App Connect Enterprise

Productinfo

Name

NLTK

Version

License

open-source

Website

Product: https://github.com/nltk/nltk/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Missing authentication
CWE: CWE-306 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 303260
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-33231

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: bbaae83db86a0f49e00f5b0db44a7254c268de9b

Timelineinfo

03/18/2026 CVE reserved
03/21/2026 +3 days Advisory disclosed
03/21/2026 +0 days VulDB entry created
03/28/2026 +7 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-jm6w-m3j8-898g
Status: Confirmed

CVE: CVE-2026-33231 (🔒)
GCVE (CVE): GCVE-0-2026-33231
GCVE (VulDB): GCVE-100-352233
CERT Bund: WID-SEC-2026-0895 - IBM App Connect Enterprise: Mehrere Schwachstellen

Entryinfo

Created: 03/21/2026 07:43
Updated: 03/28/2026 04:46
Changes: 03/21/2026 07:43 (65), 03/22/2026 11:18 (2), 03/27/2026 06:05 (1), 03/28/2026 04:46 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.