PT-2026-55683 · Nltk · Nltk/Nltk

Published 2026-07-04 · Updated 2026-07-04 · CVE-2026-12252

NVD

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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.

Fix

Code Injection

Weakness Enumeration

CWE-94

Related Identifiers

CVE-2026-12252

Affected Products

Nltk/Nltk

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-12252 · Security Note
• https://huntr.com/bounties/f5c93982-0cc9-4e2e-bb85-1b6ab29a2efb · Note
• https://twitter.com/UpwindMDR/status/2073307972738875438 · Twitter Post