CVE-2026-65915

NLTK versions before 3.10.0 contain a logic bug in FileSystemPathPointer.open() where the sandbox validation check compares a normalized path against itself, making the security check permanently inert. Attackers can pass file:// URLs to nltk.data.load() to read arbitrary files accessible to the process user, including credentials and configuration files.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

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-72r2-7mfr-5xr9	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/nltk-before-arbitrary-file-read-via-filesystempathpointer	Third Party Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-72r2-7mfr-5xr9	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 18:39

NVD link : CVE-2026-65915

Mitre link : CVE-2026-65915

CVE.ORG link : CVE-2026-65915

JSON object : View

Products Affected

nltk

nltk

CWE

CWE-284

Improper Access Control

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