CVE-2026-63312 (GCVE-0-2026-63312)

Vulnerability from cvelistv5 – Published: 2026-08-22 14:12 – Updated: 2026-08-24 18:34
VLAI
Title
NLTK StreamBackedCorpusView Bypasses pathsec.ENFORCE Arbitrary File Read
Summary
NLTK before 3.10.0 contains an arbitrary local file read vulnerability in StreamBackedCorpusView that bypasses pathsec.ENFORCE by calling builtins.open() directly instead of pathsec.open(). Attackers who control the fileid argument can read arbitrary local files regardless of the ENFORCE setting, including sensitive system files and application credentials.
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-24 18:34 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6762 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nltk nltk Affected: 0 , < 3.10.0 (semver)
Unaffected: 3.10.0 (semver)
    cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-07 00:00
Credits
Show details on NVD website

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