CVE-2026-70626

What it is

NLTK versions before 3.9.4 contain a symlink escape vulnerability in CorpusReader.open() that allows local attackers to read arbitrary files outside the corpus root. The vulnerability exists because path validation is lexical and does not account for symlink resolution, enabling attackers to place symlinks inside the corpus root to access files outside the intended boundary.

At a glance

Exploitability

Can be exploited locally on the machine without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-08-22 15:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-14 13:10 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.2% in the next 30 days (EPSS).
• Severity: 8.6 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-08-22 15:16 UTC

Last modified

2026-10-14 13:10 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-59

Record status

Analyzed

Affected

• Nltk < 3.9.4

Attack profile CVSS 4.0 · 8.6

Attack vector

Local

Complexity

Low

Attack requirements

None

Privileges needed

None

User interaction

None

Confidentiality

High

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-70626.md and follow it. Check whether this project is affected by CVE-2026-70626. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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