7.5High
Nltk Nltk
CVE-2026-62384
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.
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 0.6% chance of attack attempts being seen in the next 30 days, ranking above 45% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Nltk, and which version. The affected versions are listed further down this page.
- 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-22
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-08-22
- Last modified
- 2026-09-02
- Sources
- NVD
Affected products
- Nltk Nltk3.10.0 - 3.10.2
As listed in the NVD configuration data. Not a statement about your estate.