CVE-2026-79676

NLTK versions before 3.10.3 contain a path traversal vulnerability in corpus readers that reopen root-derived paths using built-in open() instead of nltk.pathsec.open(), allowing symlinks to escape trusted roots. Attackers who stage symlinked corpus files under a trusted data root can disclose outside-root content through normal corpus reader methods like channels(), domains(), and synonyms().

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

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-p4rw-rvv2-7xwr	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/nltk-before-path-traversal-via-symlink-bypass	Third Party Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-p4rw-rvv2-7xwr	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-08-25 16:17

Updated : 2026-08-31 19:06

NVD link : CVE-2026-79676

Mitre link : CVE-2026-79676

CVE.ORG link : CVE-2026-79676

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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