Link following in Natural Language Toolkit - #VU141416
Published: August 11, 2026
Vulnerability identifier: #VU141416
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-59
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to improper link resolution before file access in IPIPANCorpusReader _get_tag() when processing caller-supplied fileids that reference a symlink within the corpus root. A local user can place a symlinked file in a reachable corpus directory and trigger file reading through channels(), domains(), categories(), or fileids(channels=...) to disclose sensitive information.
Literal ../ traversal in the fileid is still blocked, so the issue is specific to symlink-based access to files outside the corpus root.
Affected software
Natural Language Toolkit
Remediation
Install security update from vendor's website.
Natural Language Toolkit - update to 3.10.2