High severity7.5NVD Advisory· Published Aug 22, 2026· Updated Aug 31, 2026
CVE-2026-63312
CVE-2026-63312
Description
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
nltkPyPI | < 3.10.0 | 3.10.0 |
Affected products
1Patches
Vulnerability mechanics
References
8- github.com/nltk/nltk/security/advisories/GHSA-x5ph-mj9p-rfr8nvdExploitVendor AdvisoryWEB
- github.com/advisories/GHSA-x5ph-mj9p-rfr8ghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-63312ghsaADVISORY
- www.vulncheck.com/advisories/nltk-streambackedcorpusview-bypasses-pathsec-enforce-arbitrary-file-readnvdThird Party AdvisoryWEB
- github.com/nltk/nltk/commit/674ea75accdf08eca3782dee0a9c4ed7e0d0025bghsaWEB
- github.com/nltk/nltk/pull/3588ghsaWEB
- github.com/nltk/nltk/releases/tag/v3.10.0ghsaWEB
- github.com/pypa/advisory-database/tree/main/vulns/nltk/PYSEC-2026-3730.yamlghsaWEB
News mentions
1- NLTK: Thirteen Path Traversal, RCE, and DoS Vulnerabilities Disclosed TogetherVypr Intelligence · Aug 22, 2026