CVE-2026-109956

NLTK through 3.10.3 contains a path traversal vulnerability in WekaClassifier that allows attackers to bypass nltk.pathsec containment by supplying unvalidated model paths. Attackers controlling the model_filename or model argument can make the weka JVM write files via -d or probe files via -l outside allowed data roots.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/security/advisories/GHSA-j456-xh4h-cpf2
https://www.vulncheck.com/advisories/nltk-through-3.10.3-path-traversal-via-wekaclassifier-model-path
https://github.com/nltk/nltk/security/advisories/GHSA-j456-xh4h-cpf2

Configurations

No configuration.

History

26 Oct 2026, 20:17

Type	Values Removed	Values Added
References	~~() https://github.com/nltk/nltk/security/advisories/GHSA-j456-xh4h-cpf2 -~~	() https://github.com/nltk/nltk/security/advisories/GHSA-j456-xh4h-cpf2 -

13 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 14:17

Updated : 2026-10-26 20:17

NVD link : CVE-2026-109956

Mitre link : CVE-2026-109956

CVE.ORG link : CVE-2026-109956

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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