CVE-2026-62384 PUBLISHED

NLTK FramenetCorpusReader Symlink Sandbox Bypass before 3.10.2

Assigner: VulnCheck
Reserved: 13.07.2026 Published: 22.08.2026 Updated: 22.08.2026

NLTK versions before 3.10.2 contain a symlink-based sandbox bypass in FramenetCorpusReader that allows attackers to read arbitrary XML files outside the corpus root. Attackers can place symlinks with names containing no path separators inside the corpus subdirectory, which pass the path validation guard and are resolved to files outside the intended corpus root when accessed via frame_by_name(), _lu_file(), or doc() methods.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CVSS Score: 8.7

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	None	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 7.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	nltk
Product	nltk
Versions	Default: unaffected affected from 3.10.0 to 3.10.2 (excl.) Version 3.10.2 is unaffected

Credits

LiteshGhute reporter

References

Problem Types

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE