CVE-2026-63312

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/security/advisories/GHSA-x5ph-mj9p-rfr8	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/nltk-streambackedcorpusview-bypasses-pathsec-enforce-arbitrary-file-read	Third Party Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-x5ph-mj9p-rfr8	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-22 15:16

Updated : 2026-08-31 18:40

NVD link : CVE-2026-63312

Mitre link : CVE-2026-63312

CVE.ORG link : CVE-2026-63312

JSON object : View

Products Affected

nltk

nltk

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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