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.
References
| Link | Resource |
|---|---|
| https://huntr.com/bounties/49ecbc02-054e-4470-b2e0-b267936cc4e4 | Exploit Third Party Advisory |
| https://huntr.com/bounties/49ecbc02-054e-4470-b2e0-b267936cc4e4 | Exploit Third Party Advisory |
Configurations
History
06 Mar 2026, 21:23
| Type | Values Removed | Values Added |
|---|---|---|
| Summary |
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| CPE | cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:* | |
| First Time |
Nltk nltk
Nltk |
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| References | () https://huntr.com/bounties/49ecbc02-054e-4470-b2e0-b267936cc4e4 - Exploit, Third Party Advisory |
18 Feb 2026, 20:18
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://huntr.com/bounties/49ecbc02-054e-4470-b2e0-b267936cc4e4 - |
18 Feb 2026, 18:24
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-02-18 18:24
Updated : 2026-03-06 21:23
NVD link : CVE-2025-14009
Mitre link : CVE-2025-14009
CVE.ORG link : CVE-2025-14009
JSON object : View
Products Affected
nltk
- nltk
CWE
CWE-94
Improper Control of Generation of Code ('Code Injection')
