CVE-2019-14751
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (5.67%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 5.67% probability · 93th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Affected
- nltk/nltk
- Source
- cve@mitre.org
EPSS 5.7% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- 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_PoCExploit, Patch, Third Party Advisory
- https://github.com/nltk/nltk/blob/3.4.5/ChangeLogRelease Notes
- https://github.com/nltk/nltk/commit/f59d7ed8df2e0e957f7f247fe218032abdbe9a10Patch
- 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/Exploit, Patch, Third Party Advisory
- 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_PoCExploit, Patch, Third Party Advisory
- https://github.com/nltk/nltk/blob/3.4.5/ChangeLogRelease Notes
- https://github.com/nltk/nltk/commit/f59d7ed8df2e0e957f7f247fe218032abdbe9a10Patch
- 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/Exploit, Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.