Bug 2440724 (CVE-2025-14009) - CVE-2025-14009 nltk: Zip Slip Vulnerability in nltk Leading to Code Execution
Summary: CVE-2025-14009 nltk: Zip Slip Vulnerability in nltk Leading to Code Execution
Keywords:
Status: NEW
Alias: CVE-2025-14009
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On: 2440819 2440820 2440821
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-02-18 19:03 UTC by OSIDB Bzimport
Modified: 2026-02-18 23:26 UTC (History)
22 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
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Description OSIDB Bzimport 2026-02-18 19:03:51 UTC
A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.


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