nltk up to 3.9.2 nltk.util filestring absolute path traversal

CVSS Meta Temp Score
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CTI Interest Score
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7.8$0-$5k0.00

Summaryinfo

A vulnerability was found in nltk up to 3.9.2. It has been classified as critical. This affects the function filestring of the component nltk.util. This manipulation causes absolute path traversal. The identification of this vulnerability is CVE-2026-0846. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in nltk up to 3.9.2 and classified as critical. Affected by this vulnerability is the function filestring of the component nltk.util. The manipulation with an unknown input leads to a absolute path traversal vulnerability. The CWE definition for the vulnerability is CWE-36. The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize absolute path sequences such as "/abs/path" that can resolve to a location that is outside of that directory. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attackers to access sensitive system files by providing absolute paths or traversal paths. This vulnerability can be exploited locally or remotely, particularly in scenarios where the function is used in web APIs or other interfaces that accept user-supplied input.

It is possible to read the advisory at huntr.com. This vulnerability is known as CVE-2026-0846 since 01/11/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/01/2026). The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 316734 (Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 26.04 LTS : NLTK vulnerabilities (USN-8302-1)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (316734). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.8

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CNA Base Score: 8.6
CNA Vector (@huntr_ai): 🔒

CVSSv2info

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

Exploitinginfo

Class: Absolute path traversal
CWE: CWE-36 / CWE-22
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 316734
Nessus Name: Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 26.04 LTS : NLTK vulnerabilities (USN-8302-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/11/2026 CVE reserved
03/09/2026 +57 days Advisory disclosed
03/09/2026 +0 days VulDB entry created
07/01/2026 +114 days VulDB entry last update

Sourcesinfo

Advisory: huntr.com
Status: Not defined

CVE: CVE-2026-0846 (🔒)
GCVE (CVE): GCVE-0-2026-0846
GCVE (VulDB): GCVE-100-349879

Entryinfo

Created: 03/09/2026 23:29
Updated: 07/01/2026 20:29
Changes: 03/09/2026 23:29 (61), 03/12/2026 23:55 (1), 05/26/2026 22:38 (2), 07/01/2026 20:29 (11)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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