CVE-2026-70626

NLTK versions before 3.9.4 contain a symlink escape vulnerability in CorpusReader.open() that allows local attackers to read arbitrary files outside the corpus root. The vulnerability exists because path validation is lexical and does not account for symlink resolution, enabling attackers to place symlinks inside the corpus root to access files outside the intended boundary.

CVSS v3 6.2 MEDIUM

6.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.5 / Impact : 3.6

Attack Vector LOCAL

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-r6gq-whwq-mvg9	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/nltk-before-symlink-escape-via-corpusreader	Vendor Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-r6gq-whwq-mvg9	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 19:09

NVD link : CVE-2026-70626

Mitre link : CVE-2026-70626

CVE.ORG link : CVE-2026-70626

JSON object : View

Products Affected

nltk

nltk

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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