Directory Traversal Affecting nltk package, versions <3.4.5-1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-ECHOLATEST-NLTK-18321527
- published27 Jul 2026
- disclosed22 Aug 2019
Introduced: 22 Aug 2019
CVE-2019-14751 (opens in a new tab)How to fix?
Upgrade Echo:latest nltk to version 3.4.5-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream nltk package and not the nltk package as distributed by Echo.
See How to fix? for Echo:latest relevant fixed versions and status.
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.
References
- https://advisory.echohq.com/cve/CVE-2019-14751
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QI4IJGLZQ5S7C5LNRNROHAO2P526XE3D/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZGZSSEJH7RHH3RBUEVWWYT75QU67J7SE/
- http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00054.html
- http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00001.html
- https://github.com/mssalvatore/CVE-2019-14751_PoC
- https://github.com/nltk/nltk/blob/3.4.5/ChangeLog
- https://github.com/nltk/nltk/commit/f59d7ed8df2e0e957f7f247fe218032abdbe9a10
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QI4IJGLZQ5S7C5LNRNROHAO2P526XE3D/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZGZSSEJH7RHH3RBUEVWWYT75QU67J7SE/
- https://salvatoresecurity.com/zip-slip-in-nltk-cve-2019-14751/