GHSA-q5h6-fcf5-49g9

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Source
https://github.com/advisories/GHSA-q5h6-fcf5-49g9
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-q5h6-fcf5-49g9/GHSA-q5h6-fcf5-49g9.json
JSON Data
https://api.test.osv.dev/v1/vulns/GHSA-q5h6-fcf5-49g9
Downstream
CGA (8)
Withdrawn
2026-08-13T20:44:55Z
Published
2026-06-30T03:37:14Z
Modified
2026-08-13T21:00:11Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
Summary
Duplicate Advisory: Arbitrary File Read via Path Traversal in nltk.data.load() through Percent-Encoded Sequences
Details

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-m42h-3232-vpv3. This link is maintained to preserve external references.

Original Description

NLTK version 3.9.4 is vulnerable to a path traversal attack due to an incomplete fix for GitHub Issue #3504. The _UNSAFE_NO_PROTOCOL_RE regex in nltk/data.py checks for literal ../ sequences but fails to account for percent-encoded traversal sequences such as ..%2f. The url2pathname() function decodes these sequences after the validation step, allowing an attacker to bypass the protection. This vulnerability enables an attacker to read arbitrary files accessible to the Python process by controlling the resource name parameter passed to nltk.data.load() or nltk.data.find(). The issue affects applications that rely on NLTK for resource loading, including NLP web applications, Jupyter notebooks, and CLI tools. The default pathsec.ENFORCE=False setting exacerbates the impact by not blocking the file read at the open() stage.

Database specific 
{
    "cwe_ids":  [
        "CWE-22"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-08-13T20:44:55Z",
    "nvd_published_at":  "2026-06-30T01:16:29Z",
    "severity":  "HIGH"
}
References

Affected packages

PyPI / nltk

Package

Name
nltk
View open source insights on deps.dev
Purl
pkg:pypi/nltk

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.0.1rc2-git
2.0b4
2.0b5
2.0b6
2.0b7
2.0b8
2.0b9
2.0.1rc1
2.0.1rc3
2.0.1rc4
2.0.1
2.0.2
2.0.3
2.0.4
2.0.5
0.*
0.8
0.9
0.9.3
0.9.4
0.9.5
0.9.6
0.9.7
0.9.8
0.9.9
3.*
3.0.0b1
3.0.0b2
3.0.0
3.0.1
3.0.2
3.0.3
3.0.4
3.0.5
3.1
3.2
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.3
3.4
3.4.1
3.4.2
3.4.3
3.4.4
3.4.5
3.5b1
3.5
3.6
3.6.1
3.6.2
3.6.3
3.6.4
3.6.5
3.6.6
3.6.7
3.7
3.8
3.8.1
3.9b1
3.9
3.9.1
3.9.2
3.9.3
3.9.4
3.10.0
3.10.1
3.10.2
3.10.3

Database specific

last_known_affected_version_range 
"< 3.10.0"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-q5h6-fcf5-49g9/GHSA-q5h6-fcf5-49g9.json"