CVE-2019-14751

Publication date 20 August 2019

Last updated 25 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

NLTK Downloader before 3.4.5 is vulnerable to a directory traversal, allowing attackers to write arbitrary files via a ../ (dot dot slash) in an NLTK package (ZIP archive) that is mishandled during extraction.

From the Ubuntu Security Team

It was discovered that NLTK mishandled crafted ZIP archives during extraction. A remote attacker could use this vulnerability to write arbitrary files to the filesystem

Status

Package Ubuntu Release Status
nltk 19.04 disco
Fixed 3.4-1ubuntu0.1
18.04 LTS bionic
Fixed 3.2.5-1ubuntu0.1
16.04 LTS xenial
Fixed 3.1-1ubuntu0.1
14.04 LTS trusty
Fixed 2.0~b9-0ubuntu4.1~esm2

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
nltk

Severity score breakdown

Parameter Value
Base score 7.5 · High
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact High
Availability impact None
Vector CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References

Related Ubuntu Security Notices (USN)

Other references