Most recent entries from all

BREW-acronym-CVE-2026-79674 — NLTK: Corpus Reader Sandbox Bypass

Affected: Homebrew: acronym

## Summary

NLTK corpus-reader constructors can still reach outside-root file and database reads before the `nltk.pathsec` sandbox boundary is enforced.

The PoC shows the safe path blocked by `pathsec.open`, then `LinThesaurusCorpusReader` and `PanLexLiteCorpusReader` succeeding in the same process.

## Affected Product

- Product: NLTK - Asset / component: `nltk.corpus.reader` constructors - Version tested: `3.10.2` - Deployment / package / tag: commit `474af1f5a94b1b8d53fc2b6defec3a2ce7633b74` / PyPI `nltk` - Environment used for verification: Python 3.13.14

## Vulnerability Details

- Vulnerability class: path sandbox bypass / external control of file path - Required privileges: none beyond the ability to supply a corpus root path to a consumer call site - Entry point: `LinThesaurusCorpusReader(root)` and `PanLexLiteCorpusReader(root)` - Trust boundary crossed: NLTK data-root sandbox enforced by `nltk.pathsec` - Root affected functions: - [CorpusReader.__init__](https://github.com/nltk/nltk/blob/474af1f5a94b1b8d53fc2b6defec3a2ce7633b74/nltk/corpus/reader/api.py#L73-L80) - [LinThesaurusCorpusReader.__init__](https://github.com/nltk/nltk/blob/474af1f5a94b1b8d53fc2b6defec3a2ce7633b74/nltk/corpus/reader/lin.py#L37-L43) - [PanLexLiteCorpusReader.__init__](https://github.com/nltk/nltk/blob/474af1f5a94b1b8d53fc2b6defec3a2ce7633b74/nltk/corpus/reader/panlex_lite.py#L45-L46) - Measured unsafe effect: outside-root file/database reads still happen with `ENFORCE=True`

## Roo…

CVE-2026-79674 — NLTK 3.10.2 Path Traversal via corpus-reader constructors

Affected: nltk

NLTK versions before 3.10.3 contain a path sandbox bypass vulnerability in corpus-reader constructors that allows attackers to read files outside the intended data root. Attackers can supply arbitrary corpus root paths to LinThesaurusCorpusReader and PanLexLiteCorpusReader constructors to access filesystem content and SQLite databases outside the pathsec sandbox boundary.