CVE-2026-70626
Published:August 22, 2026
Updated:August 25, 2026
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.
Affected Packages
nltk (CONDA):
Affected version(s) >=2.0.3 <3.9.4Fix Suggestion:
Update to version 3.9.4nltk (PYTHON):
Affected version(s) >=0.8 <3.9.4Fix Suggestion:
Update to version 3.9.4Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.6
Attack Vector
LOCAL
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.2
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Improper Link Resolution Before File Access ('Link Following')
EPSS
Base Score:
0.14