7.5High

Nltk Nltk

CVE-2026-62388

NLTK versions before 3.10.0 default to ENFORCE=False in pathsec.py, causing all security validation functions to emit warnings instead of raising exceptions. Attackers can bypass path traversal and pickle deserialization protections by exploiting the disabled security controls that are only active when manually enabled.

What this means for your business

  • It affects Nltk. It matters if your company, or a supplier that handles your data, runs it.
  • Code showing how to exploit it has been published, but real attacks have not been confirmed.
  • An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.5% chance of attack attempts being seen in the next 30 days, ranking above 38% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Nltk, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
7.5 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS v4
8.7
Weakness
CWE-1188
Assigned by
disclosure@vulncheck.com

Dates

Published
2026-08-22
Last modified
2026-08-27
Sources
NVD

Affected products

  • Nltk Nltk- 3.10.0

As listed in the NVD configuration data. Not a statement about your estate.

References