# CVE-2026-70626: nltk: NLTK versions before 3.9.4 contain a symlink escape vulnerability in CorpusReader.open() that allows local attackers...

CVE-2026-70626 is fixed in nltk on 1 platform by DEBIAN-CVE-2026-70626 (version 3.10.0-1), released August 22, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-70626
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0020
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 22, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | nltk Debian 14 | 3.10.0-1 | [DEBIAN-CVE-2026-70626](https://patchblox.com/security/data/fix/linux/debian-cve-2026-70626.md) | Aug 22, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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