CVE-2026-12252
In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.
- Affected products
- Nltk
- Nltk
- ≤ 3.9.3
- Fix
- Available
- CVSS 3.0
- 7.8 HIGH
- EPSS
- 0.2% (9th percentile)
- Weakness
- CWE-94
- NVD status
- Analyzed
- Published
- 2026-07-04
No indexed exploits for CVE-2026-12252 yet
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No exploit for CVE-2026-12252 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.