CVE-2026-71514 (GCVE-0-2026-71514)
Vulnerability from cvelistv5 – Published: 2026-08-22 13:34 – Updated: 2026-08-24 19:18
VLAI
EPSS
VEX
Title
NLTK 3.9.4 through 3.10.2 Path Traversal via CrubadanCorpusReader pathsec Bypass
Summary
NLTK 3.9.4 through 3.10.2 contains a path traversal vulnerability in CrubadanCorpusReader. _load_lang_ngrams joins the corpus root with crubadan_code, the column-0 value read from the corpus table.txt mapping file, and opens the result with the builtin open() rather than the pathsec-validated opener, so os.path.join discards the root when that value is absolute and the read escapes the corpus directory without the containment check nltk.pathsec applies when ENFORCE is set. An attacker who controls a corpus package can disclose file contents outside the corpus root through lang_freq, limited to paths ending in -3grams.txt whose contents parse as token count lines.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-24 19:17 UTC
CWE
- CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/nltk/nltk/commit/10d34b3f4fe3f… | patch |
| https://github.com/nltk/nltk | product |
| https://github.com/nltk/nltk/blob/v3.10.2/nltk/co… | technical-description |
| https://www.vulncheck.com/advisories/nltk-through… | third-party-advisory |
Impacted products
Date Public
2026-08-11 00:00
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.