Vulnerability in Nltk Nltk/nltk

CVE-2026-12261

A vulnerability in `nltk.downloader` in nltk/nltk versions <= 3.9.4 allows for cross-package resource and model poisoning. The downloader extracts package archives into shared namespaces such as `corpora/` and `taggers/` instead of package…

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-12261?
CVE-2026-12261 is a medium-severity vulnerability in Nltk Nltk/nltk, classified under Improper Access Control. CVSS score: 5.3/10. Published 2026-08-07.
How severe is CVE-2026-12261?
Medium severity. CVSS v3 base score is 5.3 out of 10.